Hizen (肥前国; Hizen no kuni) was an old province of Japan which bordered on Chikuzen and Chikugo. Today the area is split into Saga and Nagasaki prefecture, although it did not include the regions of Tsushima and Iki that are now in Nagasaki.

The ancient provincial capital was located near Yamato city. Toyotomi Hideyoshi directed the invasion of Korea from the city of Nagoya, in Hizen, and the Shimabara Rebellion took place in Hizen province. During the Sengoku period, the region was divided among many daimyo, with the richest having a castle town at Saga.