WEBChiba Prefecture (千葉県, Chiba-ken) is a prefecture of Japan located in the Kantō region of Honshu. [2] . Chiba Prefecture has a population of 6,278,060 (1 June 2019) and has a geographic area of 5,157 km 2 (1,991 sq mi). Chiba Prefecture borders Ibaraki Prefecture to the north, Saitama Prefecture to the northwest, and Tokyo to the west.