Ha Tay was a province of Vietnam, in the Red River Delta. In 2008, it merged with the Hanoi municipality, which largely surrounded it. Other nearby provinces include Hung Yen lies to the east, Vinh Phuc on the north, Ha Nam on the south, and Hoa Binh, Phu Tho on the west. Its capital was Ha Dong.
It was the stronghold of the eighth century leader of Vietnam, Phung Hung.
Ethnically, its population is primarily Kinh, with a small percentage from the Muong and Dao groups.