Petaling Jaya (Malaysian: [pətalɪŋ dʒaja]), colloquially referred to as "PJ", is a city in Petaling District, in the state of Selangor, Malaysia. Originally developed as a satellite township for Kuala Lumpur, the capital of Malaysia, it is part of the Greater Kuala Lumpur area. Petaling Jaya was granted city status on 20 June 2006. It has an area of approximately 97.2 square kilometres (37.5 sq mi).

Petaling Jaya is surrounded by Kuala Lumpur to the east, Sungai Buloh to the north, Shah Alam, the capital of Selangor, and Subang Jaya to the west, and Bandar Kinrara (Puchong) to the south.

Under plans developed by Francis McWilliams, the city was developed during post-war British Malaya on a piece of 1,200 acres (486 ha) rubber estate, the Effingham Estate, around Old Klang Road to address the overpopulation of the capital Kuala Lumpur in the 1950s. Since 1952, PJ witnessed a dramatic growth in terms of population size and geographical importance. The development of Petaling Jaya commenced in 1952 with the construction of 800 houses centred on the area known as "Old Town" today.

Lieutenant-General Sir Gerald Templer (then the British High Commissioner of Malaya and Petaling District council chairman) planned for Petaling Jaya to be a satellite town to prevent people from assisting the communists; the earlier housing areas were fenced off from the surrounding area. The first two main roads built in Petaling Jaya were simply called "Jalan 1" or Road 1 and "Jalan 2" or Road 2. Road 1 was later named Jalan Templer while Road 2 was named Jalan Othman after Othman Mohamad, former Menteri Besar (Chief Minister) of Selangor.

Until the end of 1953, the town was administered by the Kuala Lumpur district officer. The Petaling Jaya Town Authority headed by N.A.J. Kennedy commenced administering Petaling Jaya in 1954. On 24 August 1959, Encik Abdul Aziz bin Haji Mohd Ali became the first Malayan to head the PJ Authority. Administratively and historically, it was considered part of Kuala Lumpur. However, Petaling Jaya ceased to be part of Kuala Lumpur when the latter became a Federal Territory on 1 February 1974. It then became a township in its own right within the state of Selangor.

Petaling Garden Berhad was the pioneer private development company, responsible for the development of some areas of Petaling Jaya. It was started in 1957 by a group of Chinese businessmen including Ang Toon Chew, Robert Kuok, Tan Kim Yeow, Tan Chin Nam, Ho Yeow Khoon and Low Boon Chian. The company went on to develop thousands of acres in Petaling Jaya more specifically, Section 5, 6 and 17, to become the townships Taman Petaling Klang and Sri Petaling to name a few. Petaling Garden was brought to the Kuala Lumpur Stock Exchange and became one of the first publicly listed Property Development Companies in Malaysia. The company was bought over by Permodalan Nasional Berhad (PNB) in the year 2007, it was valued at RM 964 million at time of purchase.

Southern Petaling Jaya, from Section 8 to PJ Old Town, had the first settlements that were established around 1953. As development progressed, Northern Petaling Jaya, on the other side of the Federal Highway was developed. The first shopping complex in Petaling Jaya was Jaya Shopping Centre (better known as Jaya Supermarket). Built in 1974, it is located in Section 14.

On 1 January 1977, following the passing of the Local Government Act the previous year, the Petaling Jaya Town Authority was reorganised to become Petaling Jaya Municipal Council or Majlis Perbandaran Petaling Jaya (MPPJ). Petaling Jaya progressed rapidly due to the massive rural-urban migration. As more people from rural areas immigrated, Sungai Way and Subang districts along with areas such as Subang Jaya, Seksyen 52 (New Town or colloquially known as "State", the name of the first, former cinema in the area) developed in areas under the jurisdiction of the municipality.

Following a boundary realignment exercise in January 1997, parts of Petaling Jaya including Subang Jaya, USJ, Putra Heights, and Bandar Sunway were ceded to the newly formed Subang Jaya Municipal Council or MPSJ at the time. In exchange, the MPPJ annexed Bandar Utama, Sungai Buloh, Bukit Lanjan, and Kota Damansara from the Petaling District Council (Majlis Daerah Petaling, MDP), which disestablished itself after the cession.

Due to the proximity of the city to the capital of Malaysia, Petaling Jaya had and have been the headquarters of many federal government departments such as the Jabatan Pendaftaran Negara (National Registration Department, 1958–2004), the Jabatan Arkib Negara Malaysia (Malaysian National Archive Department, 1961–1982), and the Jabatan Kimia Malaysia (Malaysian Chemistry Department, 1957–).

In 2020, the city was part of the nationwide COVID-19 lockdown, or the movement control order (MCO), where residents were confined to their homes and only allowed out for essential purposes.

On April 27, the market in the city's oldest quarter, Old Town, was shut down down after a seafood trader there tested positive for the virus, prompting health authorities to call for customers to get themselves screened.

Less than two weeks later, large parts of Old Town came under a full government lockdown on May 10 after the discovery of 26 COVID-19 cases from the market area. Over 2,900 people in the quarter were fenced in and prevented from leaving the area, as authorities cordoned off 40ha of the area with barb wire from the rest of the city. Scheduled to last until May 23, the lockdown was eventually lifted on May 21.

After a lull in cases thanks to a nationwide lifting of restrictions, the city began to see a rise in cases in October following a spike in virus infections after infections rose in the eastern state of Sabah, where elections were held in September.

Over 800 people working at the Tropicana Golf and Country Resort were barred from leaving their hostel, as authorities put the compound under a total lockdown. Five people there tested positive for Covid 19, including two who had just returned from the eastern state of Sabah.

In the first two weeks of the month, at least four malls in the city reported COVID-19 infections. This included the 1Utama shopping mall, which was ordered to close for seven days from October 12.

Meanwhile, a teacher at the Taman Sea secondary school also tested positive for the virus on October 7, leading students and staff members there to self-quarantine. A few days later, education authorities in the country ordered 298 schools in Selangor state's Petaling district, which include Petaling Jaya, Shah Alam and Subang Jaya, to shut down from Oct 12 to Oct 25 as COVID-19 cases in the country rose.

Petaling Jaya is one of the wettest cities in Malaysia. It is warm with an average maximum of 30 degrees Celsius and receives heavy rainfall all year round, roughly more than 3,300 mm (130 in) of average rainfall annually. The city has no particular true dry season, but June and July are the driest months. Mostly each month average rainfall receives more than 200 mm (7.9 in). Thunderstorms and extreme rainstorms are common, and it is one of the highest lightning strike areas in the world. But due to normal global temperature variations, Petaling Jaya is experiencing severe drought with frequent water rationing among neighbourhoods.

The local administration of Petaling Jaya is carried out by Petaling Jaya City Council (Majlis Bandaraya Petaling Jaya, MBPJ), formerly known as Petaling Jaya Authority from 1954 until 1977 and Petaling Jaya Municipal Council (Majlis Perbandaran Petaling Jaya, MPPJ) from 1977 until 2006. Six mayors have been appointed since Petaling Jaya was awarded city status on 20 June 2006. The current mayor is Mohamad Azhan Md. Azmir, who has been in office since 21 October 2021.

The residents of Petaling Jaya are served by four Members of Parliament from Pakatan Harapan, which is DAP's Gobind Singh Deo in Damansara, PKR's Lee Chean Chung in Petaling Jaya, PKR's Ramanan Ramakrishnan in Sungai Buloh and PKR's Wong Chen in Subang.

Petaling Jaya is divided into several sections. Some are subdivided into smaller neighbourhoods (kejiranan), for example SS5D. Some sections have their own names (SS1 as Kampung Tunku), while other sections are grouped together (SS3, SS4, SS5, SS6 and SS7 as part of Kelana Jaya). Besides that, Petaling Jaya also comprises the affluent township of Damansara. SS is not the same as Seksyen but as the short acronym for Sungai Way-Subang instead.

As of 2014, Petaling Jaya claimed 613,977 residents living in the area of 51.4 square kilometres (19.8 square miles). The actual population by 2015 would have been a little over 550,000 residents without taking into account the total population of the Kuala Lumpur-Petaling Jaya conurbation which would have resulted in a total population of 1.5 million.

A prominent landmark in PJ is the Kota Darul Ehsan arch which symbolically marks the boundary between Kuala Lumpur and Petaling Jaya. This arch straddled the Federal Highway (Lebuhraya Persekutuan) which was originally the only highway link between Petaling Jaya and Kuala Lumpur. However, many links now exist as alternatives to the congested Federal Highway.

Close to the Kelana Jaya Line's Taman Jaya station is the Petaling Jaya Museum, as well as the Thai Wat Chetawan temple. This ornate building is very popular amongst the Buddhist community. A short drive ahead is PJ State, the nickname for the Central Business District of Petaling Jaya with the landmark Menara MBPJ as a focal point. PJ State is more formally referred to as PJ New Town.

The 1980s saw the establishment of shopping malls like The Atria in Damansara Jaya and Subang Parade in the nearby suburb or satellite town of Subang Jaya. The Atria provided the opportunity for residents to patronise either the Japanese Kimisawa or the French Printemps department stores, as well as a Burger King restaurant.

In 1995, 1 Utama commenced operations at Bandar Utama. Jaya Jusco, a Japanese department store which had operated since 1984 at Taman Tun Dr Ismail later relocated as one of the anchor tenants of 1 Utama.

Lotus's (formerly Tesco) supermarket commenced operations in Mutiara Damansara in 2003. This was quickly followed by the Ikano Power Centre (now renamed as IPC Shopping Centre) in 2004 and The Curve in 2005. At about the same time, the 1 Utama new wing had commenced operations, which then became the largest shopping mall in Malaysia (or currently 12th largest shopping mall in the world).

In 2004, Giant Hypermarket commenced operations in Kelana Jaya. This complex houses the Giant Hypermarket and some shops to create a more shopping centre style. It was easily accessed off the Damansara–Puchong Expressway. It was eventually closed down permanently on 26 November 2023 as the land was bought by a developer to make way for a new condominium. Located right opposite across the LDP is Paradigm Mall, which opened in mid-2012. Paradigm Mall was developed by WCT on the former Kelana Jaya garbage landfill.

Cambridge Analytica claimed to have an office in Kota Damansara; checks shown that the reported address was used for residential purpose.

Active property developers in Petaling Jaya are PKNS, Sunway Bhd, Tropicana Bhd, AmCorp, Mah Sing Group and Guocoland as well as many others. Due to the size of Petaling Jaya township, property development in the area also includes small to medium-sized developers such as Sri Aman Development and Nusmetro.

Before the rapid development and commercialisation of Petaling Jaya, there were only a handful of residential developments that comprises mostly low to medium-cost apartments as well as terrace houses. By 2005, luxurious condominiums, semi-detached houses, and bungalows are a common sight within the area. These high-end properties are mostly located at Bukit Gasing, Section 16 & 17, SS7 Kelana Jaya, and more recent ones such as Tropicana, and Ara Damansara.

Bus services were initially provided by Sri Jaya between the early 1950s until the early 1990s. Some SEA Park residents may recall the old Sri Jaya Leyland Albion buses on the No. 241 service struggling to climb the relatively steep Jalan 21/1.

The introduction of the IntraKota bus system by DRB-HICOM saw the replacement of Sri Jaya and the mini-buses by the early 1990s. Around the same time, some of the Petaling Jaya-Kuala Lumpur bus routes were serviced by Metrobus.

The introduction of the PUTRA-LRT light rapid transit service in 1998 saw the addition of the Putraline feeder bus services.

The ownership of the PUTRA-LRT and its Putraline feeder bus services, as well as the IntraKota bus system, were taken over by Prasarana Malaysia in 2002 and 2004 respectively, eventually transferring all rail and bus operations to the Rapid KL system. Today, most of the public transportation in the form of busses in Petaling Jaya is operated by Rapid Bus under the Rapid KL brand, which also operates bus services in Kuala Lumpur and the rest of the Klang Valley area. Rapid Bus also operates the PJ City Bus, a free bus service funded by the Petaling Jaya City Council.

There are currently three rapid transit lines and one commuter rail line serving Petaling Jaya. These lines also provide connections to a bus rapid transit line and a inter-city rail service.

The PUTRA-LRT line, subsequently renamed 5 LRT Kelana Jaya Line and currently operated by Rapid Rail under the Rapid KL brand, has a total of seven stations serving central and southern Petaling Jaya, which are the Taman Jaya, Asia Jaya, Taman Paramount, Taman Bahagia, Kelana Jaya, Lembah Subang and Ara Damansara stations.

The newly constructed 9 MRT Kajang Line and 12 MRT Putrajaya Line, which opened in 2017 and 2022 respectively, serve the northern part of Petaling Jaya's municipal area, also known as Damansara. The lines call at Kota Damansara, Surian, Mutiara Damansara and Bandar Utama on the Kajang Line, and the Damansara Damai, Sri Damansara Barat, Sri Damansara Sentral and Sri Damansara Timur stations on the Putrajaya Line.

In the future, the upcoming 11 LRT Shah Alam Line, will serve twenty-six stations in central and western Petaling Jaya starting from Bandar Utama, Glenmarie 2, SS7 to Johan Setia. The railway line set to open in 2025.

The 2 Tanjung Malim-Port Klang Line, a commuter rail service operated by KTM Komuter, mainly serves southern Petaling Jaya via Petaling, Jalan Templer, Kampung Dato Harun, Seri Setia and Setia Jaya stations. At the Setia Jaya, the KTM Komuter line is connected to the B1 BRT Sunway Line. (Sunway-Setia Jaya station).

Despite their names, the Sungai Buloh and Kepong Sentral stations are both located within the Petaling Jaya City Council's jurisdiction, and as such, are part of the Petaling Jaya city proper. These stations are both served by the 2 Tanjung Malim-Port Klang Line, as well as the  ETS  KTM ETS, an inter-city rail service providing services to Padang Besar, Butterworth, Ipoh and Gemas. The 12 MRT Putrajaya Line also calls at Sungai Buloh station.

Petaling Jaya has three access points to the national highway system: North–South Expressway Northern Route via Kota Damansara, Damansara, and Subang. Internally, highways such as the Damansara–Puchong Expressway, Sprint Expressway and the FT 2 Federal Highway exist and also known for traffic jams.

Petaling Jaya is also served by the Sultan Abdul Aziz Shah Airport which is located immediately to the west of Petaling Jaya.

There are more than 25 colleges and universities in Petaling Jaya including International Islamic University Malaysia (IIUM/UIAM) centre for foundation studies campus in Section 17, SAITO University College in PJ New Town, MARA University of Technology (UiTM) campus branch on Jalan Othman in Section 1, Tun Abdul Razak University (UNITAR) main campus in SS6 Kelana Jaya, Stamford College on Jalan Timur and Jalan 223 (moved out, no longer there), Food Institute of Malaysia (FIM) in SS6 Kelana Jaya, Lincoln University College, Malaysia University of Science & Technology (MUST) main campus in SS7, Kolej Bandar Utama (KBU) in Bandar Utama, IACT College at Damansara Utama, Brickfields Asia College at Section 14, SEGi University at Kota Damansara, and International University College Of Technology Twintech a private college at Bandar Sri Damansara. TCA College (Malaysia) (TCAM) is an interdenominational Charismatic Bible College, and City University Malaysia main campus in Section 51a near LRT Asia Jaya.

The UiTM facility in Section 1 commenced life as the Dewan Latehan RIDA in November 1956. It was later renamed the Dewan Latihan MARA. This was a training centre under the auspices of RIDA or the Rural and Industrial Development Authority. Essentially it was also the inspiration of Dato' Onn Jaafar, the founder and former president of UMNO or the United Malays National Organisation. This UiTM facility can be regarded as Petaling Jaya's oldest college.

There are 58 primary and 28 secondary schools in Petaling Jaya under the purview of Malaysian Ministry of Education including

• SK Kampung Tunku
• SK Kelana Jaya
• SK Sri Damai
• SMK Taman SEA
• SMK Damansara Utama
• SMK (L) Bukit Bintang
• SMK (P) Assunta
• SMK (P) Sri Aman
• SMJK (C) Katholik
• SMK (L) La Salle
• SMK Damansara Jaya
• SMK Bandar Utama Damansara 3
• SMK Sultan Abdul Samad
• SMK Taman Medan
• SMK (P) Taman Petaling
• SMK Kelana Jaya.

The oldest schools in Petaling Jaya are likely the Road 10 Primary School in Old Town, followed by Assunta in 1955 by the Franciscan Missionaries of Mary and La Salle in 1959 by the De La Salle Brothers. The foundation stone of the Road 10 school was placed by Sultan Hisamuddin Alam Shah in 1952.

The German School Kuala Lumpur, a German international school, is in Petaling Jaya.

Malaysia's first private nursing college is at Assunta Hospital in Petaling Jaya. The Tun Tan Cheng Lock College of Nursing was founded in 1961.

Petaling Jaya has a fully equipped, multi-purpose stadium known as Petaling Jaya Stadium. Petaling Jaya Stadium is the home of Petaling Jaya City F.C. and Petaling Jaya Rangers, and has a capacity of 25,000. Selangor F.C. is currently using the stadium for their home games while their official home stadium, Shah Alam Stadium, was supposed to undergo a major transformation but there are concerns that the stadium could be demolished to make way for an entirely new state-of-the-art facility.

The Headquarter of Football Association of Malaysia (FAM) is also located in Petaling Jaya.

Petaling Jaya is the headquarters for newspaper and online news companies such as: Free Malaysia Today, Malay Mail, Malaysiakini, Nanyang Siang Pau, Sin Chew Daily, Star Media Group (Menara Star), The Edge Media Group (Menara KLK), The Malaysian Reserve and The Sun Daily and the radio and television division of Media Prima Berhad (Sri Pentas), all of them are located near Kuala Lumpur.

Mosques are located at Jalan Templer, Section 17, Section 14, Section SS1, and Damansara Utama. Masjid Kelana Jaya Putera, which was built in the late-2000s, is located in Kelana Jaya. Masjid Jamek Sultan Abdul Aziz Shah at Jalan Templer is likely the oldest mosque in Petaling Jaya. This mosque was opened by the Sultan of Selangor on 23 October 1964. Later in 2008, the mosque was modernised and rebuilt.

The Roman Catholic Christian community attend mass at churches such as at St Francis Xavier's, located on Jalan Gasing, this church was established in 1961. Two other Catholic churches are the Church of the Assumption on Jalan Templer as well as St. Ignatius in Taman Mayang. The Assumption church is the oldest, it dates from 1959. The Trinity Methodist church dates from 2 August 1959 and is at Jalan 5/37. An Anglican as well as a Lutheran church is located at Jalan Utara. Glad Tidings Assembly of God church is at Jalan Bersatu 13/4. Several shophouse-based churches exist across Petaling Jaya. In 2005, the former Ruby Cinema in SEA Park temporarily became the Damansara Utama Methodist Church. DUMC later relocated to its permanent building located in Section 13. Harvest Community Church (an Assembly of God church) is located at Jalan Sungai Jernih. Small "shoplot" churches can be found all around the city; some of these have transformed into larger churches, such as the Grace Assembly (an Assembly of God church). These attract a larger following and can be found in many places around the city. There is also Acts Church's service plants located inside the Jaya One shopping mall. Kingdomcity church is located in the Evolve Concept Mall.

The Thai Buddhist Temple, Wat Chetawan along Jalan Gasing was built in 1957 and officiated by the late King Bhumibol Adulyadej, King of Thailand. Chempaka Buddhist Lodge (千百家佛教居士林) was established in 1985, it is managed by the lay Buddhist community and located at Taman SEA. Chinese Buddhist temples such as Poh Lum Fatt Yuen (寶林法苑) along Jalan Gasing and Kwan Inn Teng Temple (觀音亭) are also catered for the local Chinese Buddhist community. Hung Shing Temple (洪聖宫廟) and Yuen Leong Sing Fatt Temple (阮梁聖佛宮) fulfill the needs of the Taoist community. Other Chinese temples such as the Yuan Lin Xiao Zhot Buddhist Temple (园林小筑) and Sau Seng Lum Buddhist Temple (修成林) can also be found in PJ Old Town and in Section 11.

The Sri Sithi Vinayagar Temple at Section 4 along Jalan Selangor serves as the main religious facility for Petaling Jaya's Hindu community. The main deity worshiped here is Pillaiyar (a common Tamil name for Ganesha). There is a Mariamman Temple in Jalan 17/47, and the Geeta Ashram is a north-Indian style Hindu Temple dedicated to Krishna. The Geeta Ashram can be found in Lorong Utara B in Section 52.

There is a Sikh Gurdwara located in Lorong Utara B, beside the Tun Hussein Onn Eye Hospital and the Geeta Ashram.

The city made international headlines on 13 February 2017 when Christian pastor, Raymond Koh was ambushed on SS4B/10 by around fifteen men in SUVs and subsequently "disappeared". Koh led the Hope Community in Kuala Lumpur which helps the city's poor, single mothers, and drug addicts. In 2019, the Human Rights Commission of Malaysia accused the Malaysian Special Branch of the abduction, carried out because Koh was suspected of attempting to convert Sunni Muslims to Christianity.

• Riad Asmat, former CEO of Caterham F1 Team in 2010–2014 was born on 17 November 1971
• Bernard Chandran, Malaysian fashion designer
• Raymond Koh, Christian pastor abducted by the Malaysian Special Branch in February 2017

Petaling Jaya currently has four sister cities:

• Petaling Jaya
• JPN Petaling Jaya
• SS20 Petaling Jaya