Ertai () is a town located in Zhangbei County, Zhangjiakou, Hebei, China. According to the 2010 census, Ertai had a population of 18,673, including 9,540 males and 9,133 females. The population was distributed as follows: 2,935 people aged under 14, 13,568 people aged between 15 and 64, and 2,170 people aged over 65.