Oaxaca (English /wəˈhɑːkə/ wə-HAH-kə, Spanish: [waˈxaka] ( listen), from Nahuatl: Huaxyacac [waːsʃakak]), officially Free and Sovereign State of Oaxaca (Spanish: Estado Libre y Soberano de Oaxaca), is one of the 31 states which, along with the Federal District, comprise the 32 federative entities of Mexico. It is divided into 571 municipalities; of which 418 (almost three quarters) are governed by the system of Usos y costumbres (customs and traditions) with recognized local forms of self governance. Its capital city is Oaxaca de Juárez.

It is located in Southwestern Mexico. It is bordered by the states of Guerrero to the west, Puebla to the northwest, Veracruz to the north, Chiapas to the east. To the south, Oaxaca has a significant coastline on the Pacific Ocean.

The state is best known for its indigenous peoples and cultures. The most numerous and best known are the Zapotecs and the Mixtecs, but there are sixteen that are officially recognized. These cultures have survived better than most others in Mexico due to the state’s rugged and isolating terrain. Most live in the Central Valleys region, which is also an important area for tourism, attracting people for its archeological sites such as Monte Albán, native culture and crafts. Another important tourist area is the coast, which has the major resort of Huatulco. Oaxaca is also one of the most biologically diverse states in Mexico, ranking in the top three, along with Chiapas and Veracruz, for numbers of reptiles, amphibians, mammals and plants.