Hi Province (火国 or 肥国, Hi no kuni) was a very old province of Japan, in the area of Hizen and Higo provinces. It was sometimes called Hishū (肥州).
The boundaries of this ancient entity are within Nagasaki (without Tsushima and Iki), Saga and Kumamoto prefectures.
The history of the province started and ended before the Taihō Code was established at the beginning of the 8th century.