Tai'an Township () is a mountain indigenous township in southeastern Miaoli County, Taiwan. It is the largest township and the only mountain indigenous township in Miaoli County.
Tai'an Township is a mountainous region without convenient transportation both between villages and between Tai'an itself and outside townships. The sources of the Houlong and Da-an rivers are found in the township. More than two thirds of the population consists of the indigenous Atayal people.
The township comprises eight villages: Bagua, Daxing, Jinshui, Meiyuan, Qingan, Shilin, Xiangbi and Zhongxing.
The township is part of Miaoli County Constituency II electoral district for Legislative Yuan.