Wao officially the Municipality of Wao (Maranao/Iranun: Inged a Wao; Cebuano: Lungsod sa Wao; Tagalog: Bayan ng Wao), is a municipality in the province of Lanao del Sur, Philippines. According to the 2020 census, it has a population of 50,366 people. Wao is the only Christian-majority municipality of its province.

There are three possible etymology for the name of the municipality Wao. One is a local folklore which involved Bai Sa Raya, a Moro princess from a monarchy in Cotawato visited the area which is now known as "Wao" coincidentally during a serious drought. This led to the place to being called Wao from the word kawaw or uhaw in the local language which roughly translates to "I am thirsty". Another theory is that the place was named after a former creek in Eastern Wao which was extant prior to the arrival of Christian settlers in the 1950s. A third theory is that the name of the town was derived from the Maranao word liawao which means "high place", this is a reference to a Moro settlement existing in the current-day poblacion during the pre-1950 settlement era. Other nearby settlements are situated at a lower elevation that Liawao.

The LASEDECO resettlement program of then-President Ramon Magsaysay made possible the foundation of Wao as a municipality in Lanao del Sur province on February 22, 1961. The first settlers in the area were sixty families of various ethnicity from the then-undivided Cotabato province. Only one person, Elvino B. Balicao Sr. among the 1st batch of settlers became one of the Municipal Mayors of Wao. Balicao, along with members of the 1st batch of 60 settlers that included the late couple Aludio and Sofia Emborgo, were welcomed by the native Muslim inhabitants of Wao led by Sultan Mamaco Saripada, the municipality's first appointed and elected mayor, Datu Tao Pagul and Datu Maki Saripada. They were treated to a sit-down meal in the house of Sultan Mamaco Saripada.

In the late 1970s, the town experienced intercommunal violence between its native Moro community and the Christian settlers. Tensions arose after Bumbaran (now known as Amai Manabilang) was created from Wao by President Ferdinand Marcos through Presidential Decree No. 1243 in November 17, 1977.

In 2024, a new municipality named Pilintangan or Saripada was proposed to be carved from Wao in the Bangsamoro Parliament, which would entail the loss of 11 barangays. This proposal was met with protests and opposition, fearing that this might cause a repeat of the violence the town experienced in the 1970s. Wao's mayor, Elvino Balicao Jr., also warned that the division would reduce the town into a third-class municipality due to reduced revenues and with most of its government buildings being located in the barangays to be separated.

Wao is also surrounded by Amai Manabilang in the north and west, Bukidnon in the east, and Cotabato in the south. Its border with Bukidnon is demarcated by the Maradugao River.

Wao is politically subdivided into 26 barangays. Each barangay consists of puroks while some have sitios.

Wao is the only predominantly Christian municipality in Lanao del Sur, with 80% of the population adhering to Roman Catholicism as of 2017, brought by these settlers who came from Luzon, Visayas and other parts of Mindanao. The Roman Catholic church administrates its constituents in Wao as part of the Bukidnon-based Diocese of Malaybalay.

Among the significant ethnic groups in Wao are the Ilonggo, Ilocano, Cebuano, Maranao, Ivatan and Tagalog peoples.

Population census of Wao

Year	Pop.	±% p.a.
1960	13,848	—
1970	16,577	+1.81%
1975	17,267	+0.82%
1980	15,962	−1.56%
1990	22,932	+3.69%
1995	27,503	+3.46%
2000	35,517	+5.63%
2007	42,186	+2.40%
2010	40,479	−1.49%
2015	45,862	+2.41%
2020	50,366	+1.86%
Source: Philippine Statistics Authority

Poverty Incidence of Wao

10 20 30 40 50 60 70 80 2000 71.44 2003 39.59 2006 27.60 2009 25.47 2012 73.80 2015 45.40 2018 65.07 2021 22.87 Source: Philippine Statistics Authority

The Wao Development Corporation (WDC) maintains a pineapple plantation and package facility in Wao.

• Quezon City, since April 1990

• Wao Profile at the DTI Cities and Municipalities Competitive Index
• Philippine Standard Geographic Code
• Local Governance Performance Management System
• Philippine Census Information