Kajang is a city in Hulu Langat District, Selangor, Malaysia, located southeast of Kuala Lumpur. Kajang, along with much of Hulu Langat District, is governed by the Kajang Municipal Council. Kajang town is located on the eastern banks of the Langat River. It is surrounded by Cheras, Semenyih, Bangi, Putrajaya and Serdang.

According to the 2020 census, the local authority area (which includes Kajang, Cheras, Balakong, Bangi, Semenyih and Pekan Hulu Langat) has a population of 1.05 million people.

The name Kajang is believed to have originated from the language of Temuan tribes (Orang Asli) who populated the Langat valley in the 17th-18th centuries. In their language kajang referred to their art of weaving screwpine or pandanus leaves, which were prevalent in much of the country. A similar theory stated that settlers from the neighboring domain of Sungai Ujong (Negeri Sembilan) once constructed huts (pondok) in the area with thatched roof made from folded (lipat kajang) screwpine leaves.

It is also believed that the name kajang may have originated from the Buginese word berkajang, meaning camp or accommodation.

Kajang is about 22 km (14 miles), about a half hour's drive, from Kuala Lumpur's central business district, primarily through Jalan Cheras and the Grand Saga Expressway; both routes are part of the Malaysia Federal Route 1 system. By railway, it is about 40 minutes' ride from KL Sentral on the MRT Kajang line.

The first planned township built and developed just outside Kajang is Bandar Baru Bangi which was first developed in 1974 by the Selangor state government. As a satellite town to Kajang proper, some government offices including the district land office begin operating out of the township. The Kajang bus and taxi terminal called Hentian Kajang is also located at the eastern end of the township.

More townships were developed closer to Kajang town in recent years, such as Taman Prima Saujana, Sungai Chua and Taman Kajang Perdana (Kajang Highlands). High-end developments in Kajang include Twin Palms, Sri Banyan, Country Heights, Jade Hills, Saujana Impian, TTDI Grove, Tropicana Heights and Prima Paramount. Areas surrounding these townships are accessible via the SILK Expressway, Kajang-Seremban Expressway, Grand Saga Expressway and the North–South Expressway Southern Route.

Some adjacent areas in the neighbouring Sepang region including Kampung Sungai Merab, Desa Pinggiran Putra and Kampung Dato Abu Bakar Baginda, though rarely regarded as part of Kajang, are included in Kajang's postal code of 43000 due to their proximity to Kajang than to Sepang town itself.

The townships in Bandar Seri Putra and Bukit Mahkota, while closer to Bangi Lama (Bangi old town) also use the postal code of Kajang. Bangi Lama, Bandar Seri Putra and Bukit Mahkota are located in Mukim Kajang.

Orang Asli tribes had already established settlements in what is now Kajang as early as the 16th century, however the first recorded settlement was found in 1709 by additional Orang Asli settlers who relocated from the Klang valley. Kajang town in its present form was founded in the 1870s, in the aftermath of the Klang War. In its early days, it was settled by Mandailings and Minangkabau people from Sumatra in the then-Dutch East Indies, followed by Chinese tin miners.

As with other towns in Selangor, Kajang as a modern town owes its rise in particular to tin mines and plantations which were opened around the 1890s. A famous coffee estates was Inch Kenneth Estate managed by the Kindersley brothers, who were among the first to plant rubber in the country on a commercial basis.

During the Japanese invasion, Kajang was bombed on 12 January 1942, a day after the fall of Kuala Lumpur. The bombs, meant for the railway station, missed its target, and hit a nearby church instead.

In 1948, a Communist insurgency against British forces and their allies across Malaya began, which led to the Malayan Emergency with fighting soon spreading to Kajang. Guerrilla leader Lau Yew died in combat just outside Kajang in July 1948; British forces photographed his corpse and printed the image onto leaflets to distribute around Kajang.

Kajang was granted municipal status on 1 January 1997. Previously it was under the jurisdiction of the Hulu Langat District Council (Majlis Daerah Hulu Langat, MDHL). Kajang was the administrative centre of the Hulu Langat region until it was relocated to Bandar Baru Bangi in 1992.

In the 2020 census, the Kajang Municipal Council is home to 1.05 million people, making it Malaysia's second most populous local authority after Kuala Lumpur. Over 350,000 people reside in Kajang town itself and its immediate suburbs.

Kajang's main population centres are Sg. Sekamat, Taman Saujana Impian, Sg. Kantan, Sg. Jelok, Sg. Ramal, Sungai Chua, Jalan Reko, Jalan Bukit, Taman Jenaris, Taman Prima Saujana, Taman Kantan Permai, Taman Kajang Perdana, Taman Sri Ramal, Taman Bukit Mewah, Kajang Prima, Bandar Teknologi Kajang, Hillpark and Bandar Baru Bangi.

Malay   43.66% Other Bumiputeras   2.46% Chinese   35.34% Indians   9.74% Others   0.6% Non-Malaysians   8.2%

The city centre of Kajang is the colonial quarter near the Stadium Kajang MRT station, including the streets of Jalan Mendaling, Jalan Stadium, Jalan Sulaiman and Jalan Raja Haroun. The buildings in the area were constructed around the 1900s to 1930s. The architecture of these shophouses are a combination of traditional Chinese and European designs. The ground floor was used mostly for commercial activities and the upper floor as the family living quarters.

One of Kajang's landmarks is Kajang Stadium which is situated in the heart of the town. The stadium can accommodate up to 5,000 people and is used throughout the year for the community soccer competitions.

Another landmark is the Kajang Jamek Mosque, which is recognisable by its bright yellow facade.

Kajang is served by a network of tolled expressways and federal highways.

Federal Route 1, the premier north–south federal route of Peninsular Malaysia, runs through downtown Kajang as Jalan Cheras from Cheras until Sungai Jernih and Stadium Kajang and then southwards as Jalan Semenyih from Stadium Kajang until Semenyih, Beranang and neighbouring Seremban, Negeri Sembilan with the rest of the route terminating in Johor Bahru, Johor - the route's southern terminus. On Federal Route 1, Kajang is 22 km from Kuala Lumpur, 8 km from Semenyih and 43 km from Seremban.

A stretch of Federal Route 1 is concurrent with the Cheras-Kajang toll road (aka the Grand Saga Expressway) between Taman Connaught and Bukit Dukung. The SILK Expressway starts in Serdang, which then runs through Balakong and then forms a beltway around downtown Kajang before ending near Bandar Baru Bangi. It is the main ring road for Kajang.

PLUS Expressway exit 210 (Kajang Interchange) serves the vicinity of Kajang and Bangi. It also links the expressway to SILK Expressway and SKVE Expressway as well as B11 which runs concurrently with SILK and SKVE from SKVE's Serdang Interchange at Seri Kembangan until SILK's Sungai Chua Interchange at Kajang, before being detoured out of SILK after the interchange. B11 continues on its own separate route until its terminus at Stadium Kajang just before the intersection with Jalan Cheras, Jalan Semenyih and Jalan Reko

From Ampang Jaya, one can reach Kajang with state routes B62 and B52.

 KB06   KG35  Kajang railway station is the principal rail station of Kajang. It is an interchange station between the 9 MRT Kajang Line, 1 KTM Seremban Line and  ETS  KTM ETS. The station is the southern terminal of the MRT line.

Kajang station, though so named, does not directly serve downtown Kajang; Stadium Kajang MRT is located in the actual downtown area, along with Sungai Jernih MRT.

Kajang is famous for its satay, a form of skewered barbecued meat. Informally, Kajang is known as the Satay Town.

The Malaysia Prison Complex (Kompleks Penjara Kajang), Prison Department of Malaysia is headquartered in Kajang.

Kajang has multiple shopping complexes, amongst them is the Billion Shopping Center formerly in Kajang town, which now has relocated to Bandar Teknologi Kajang. Other shopping centres located in Kajang are Plaza Metro Kajang, Metro Point and Kompleks Kota Kajang. Metro Avenue is a new shopping district located opposite SMJK Yu Hua Kajang and Kajang High School.

Kajang Hospital is the primary public hospital in the city.

Private medical centres function 24 hours and include facilities such as Poliklinik MUC @Metro Point, Klinik Mediviron Prima Saujana, Kajang Plaza Medical Centre (KPMC) and KPJ Kajang Specialist Hospital.

The Hulu Langat District Police Headquarters are located in the town centre, across the Highway 1 junction from the Post Office. Federal government agencies with their branch in Kajang include the National Registration Department, Immigration Department, Transportation Department, and Hulu Langat Education Office.

• Al-Amin Sungai Tangkas
• Rafflesia International School Kajang 2
• SK Bandar Seri Putra
• SK Jalan Bukit 1
• SK Jalan Bukit 2
• SK Jalan Semenyih 1
• SK Jalan Semenyih 2
• SK Kajang
• SK Kajang Utama
• SK Kantan Permai
• SK Leftenan Adnan
• SK Saujana Impian
• SK Saujana Impian 2
• SK Seri Sekamat
• SK Taman Jasmin
• SK Taman Sri Jelok
• SRJK(C) Yu Hua
• SRJK(C) Yu Hua 2 (under construction)
• SRJK(C) Sungai Chua
• SRJK(T) Kajang
• Tanarata International Schools
• SK Convent Kajang
• SK Taman Rakan

• Rafflesia International School@Kajang 2
• SMK Convent Kajang
• SM Integrasi Tahfiz Ilmuwan Bangi
• SM Rafflesia@Kajang 2
• SM Teknik Kajang
• SMAP Kajang
• SMJK Yu Hua Kajang
• SMK Jalan Bukit
• SMK Jalan Reko
• SMK Kajang Utama
• SMK Saujana Impian
• SMK Sultan Abdul Aziz Shah (SAAS)
• SMK Sungai Ramal (SEMARAK)
• SMK Taman Jasmin 2
• SMK Tinggi Kajang (Kajang High School)
• SMKA Maahad Hamidiah
• Tanarata International Schools

Kajang is home to institutions of higher learning, which includes:

• Universiti Tunku Abdul Rahman (UTAR) Sungai Long Campus
• Universiti Tenaga Nasional
• Infrastructure University Kuala Lumpur
• New Era University College
• German-Malaysian Institute
• Universiti Kuala Lumpur Malaysia France Institute (MFI)
• Universiti Kuala Lumpur Medical Science and Technology (MESTECH)
• Universiti Kebangsaan Malaysia (UKM)

Kajang is a state seat in the Selangor State Legislative Assembly and one of three state seats within the Bangi parliamentary seat in the Dewan Rakyat of the Parliament besides Balakong and Sungai Ramal. Bangi has been represented by Member of Parliament (MP) Syahredzan Johan of Pakatan Harapan (PH) since 2022 and Kajang has been represented by Member of the Legislative Assembly (MLA) David Cheong Kian Young of PH since 2023.

Before that, Kajang was one of the state seats within the Hulu Langat parliamentary seat in the Dewan Rakyat of the Parliament besides Semenyih and Dusun Tua.

• Lt Adnan Bin Saidi, Malayan military officer who took part in the Battle of Singapore, Bukit Chandu during World War II.
• Datuk Ramli bin Ibrahim, Malaysian choreographer.
• Ning Baizura, singer.
• Nora Danish, actress.
• Suresh Navaratnam, Malaysian cricketer, represented Malaysia for 21 years and captained the National Team.
• K. Sanbagamaran, former Selangor FA and Malaysia national football team player.
• D. Christie Jayaseelan, football player.
• K. Reuben, football player.
• Safee Sali, football player.

• Kajang Municipal Council Official Website