Ansai is a district of the city of Yan'an, Shaanxi province, China. It has a total area of 2,951.3 km2 (1,139.5 sq mi) and a population of 172,900 people. Part of the Loess Plateau, the district has an average elevation of 1,371.9 metres (4,501 ft). Its postal code is 717400, and its Serial Number is 610624.

Yan'an is a prefecture-level city in the Shaanbei region of Shaanxi province, China, bordering Shanxi to the east and Gansu to the west. It administers several counties, including Zhidan, which served as the headquarters of the Chinese Communists before the city of Yan'an proper took that role.