Da'an (Chinese: 大安; pinyin: Dà'ān; lit. 'Dalai and Anchang') is a city of northwestern Jilin province in Northeast China, on the southern bank of the Songhua River and the border with Heilongjiang province. It is under the administration of Baicheng City, 115 kilometres (71 mi) to the west, and lies 57 kilometres (35 mi) northwest of Songyuan. Da'an City is 423,700, including 423,000 permanent residents.

There are five subdistricts, 10 towns, 16 townships, and one ethnic township.

Subdistricts:

Towns:

Townships:

The original name of Da'an is Mole Honggangzi. In the early Qing Dynasty, it was under the jurisdiction of General Shengjing.

At the end of World War II the Soviets invaded Japanese-held Manchuria. After they withdrew from Manchuria in 1946, control of Dalai County alternated between the Communists and Nationalists, the final liberation being in January 1949. Neighbouring Anguang county remained in Communist control after liberation in February 1946. In 1958 Dalai County was merged with Anguang County and the names merged to create Da'an County.

In 1988, Da'an became a county-level city.