Fusa Province (総国 or 捄国 Fusa-no kuni) was an ancient province of Japan, in the area of Shimōsa ("Lower Fusa") and Kazusa ("Upper Fusa") provinces. At the time of the establishment of Kazusa Province, it also included the southern tip of the Bōsō Peninsula that would later be split off as Awa Province. The ambit of this ancient entity is within Chiba Prefecture and Ibaraki Prefecture. It was sometimes called Sōshū (総州).
Although Fusa Province has been divided into Shimōsa and Kazusa since ancient times, a toponym Fusa has survived into modern times as the name of a village (布佐村 Fusa-mura), later a town (布佐町 Fusa-machi), which now forms the eastern part of Abiko City along the south bank of the Tone River. There is also a Fusa Station on the Abiko branch of JR East Japan's Narita Line, located in the Fusa neighborhood of Abiko City.
- Satow, Ernest. (1874). "The Geography of Japan," Transactions of the Asiatic Society of Japan, Vol. 1-2, p. 35., p. 35, at Google Books; Nussbaum, Louis-Frédéric. (2005). "Fusa no Kuni" in Japan Encyclopedia, p. 224, p. 224, at Google Books.
- Nussbaum, "Shimosa" in p. 862, p. 862, at Google Books; "Kazusa" at p. 502, p. 502, at Google Books
- Asiatic Society of Japan. (1874). Transactions of the Asiatic Society of Japan. Yokohama: The Society. OCLC 1514456
- Nussbaum, Louis-Frédéric and Käthe Roth. (2005). Japan encyclopedia. Cambridge: Harvard University Press. ISBN 978-0-674-01753-5; OCLC 58053128