Santa Marcela, officially the Municipality of Santa Marcela (; ), is a municipality in the province of Apayao, Philippines. According to the 2024 census, it has a population of 14,049 people.
Santa Marcela was created into an independent municipality on June 17, 1967, when several barrios were separated from Luna and Flora and constituted into the newly created town.
According to the Philippine Statistics Authority, the municipality has a land area of constituting of the total area of Apayao.
Santa Marcela is situated from the provincial capital Kabugao, and from the country's capital city of Manila.
Santa Marcela is politically subdivided into 13 barangays. Each barangay consists of puroks and some have sitios.
In the 2024 census, Santa Marcela had a population of 14,049 people. The population density was .
Santa Marcela, belonging to the lone congressional district of the province of Apayao, is governed by a mayor designated as its local chief executive and by a municipal council as its legislative body in accordance with the Local Government Code. The mayor, vice mayor, and the councilors are elected directly by the people through an election which is being held every three years.
The Sta. Marcela Schools District Office governs all educational institutions within the municipality. It oversees the management and operations of all private and public, from primary to secondary schools.