Coronel Dorrego is a partido (administrative district) located on the southern coast of Buenos Aires Province in Argentina. It forms part of the province's southern coastal region, an area of the Pampas where the inland plains meet the Atlantic Ocean.
The partido is one of the administrative subdivisions of Buenos Aires Province, the most populous province in Argentina. Its seat and principal settlement is the city of Coronel Dorrego, which shares the district's name. The district's coastal position places it along the Atlantic seaboard of the province's south.
Like other partidos in the region, Coronel Dorrego is organized as a local government unit within the provincial structure of Buenos Aires Province. The area lies within the temperate grassland zone typical of the southern Pampas, near the transition to the coast.