Kōfu Castle was a Japanese castle located in the city of Kōfu, Yamanashi Prefecture, in the Chubu region of Japan. The site has been protected as a National Historic Site since 2019. The castle is also known as Maizuru Castle, and the present-day surroundings are called Maizuru Castle Park .

Kōfu is the capital city of Yamanashi Prefecture, Japan. As of 1 April 2019, the city had an estimated population of 187,985 in 90,924 households, and a population density of 880 persons per km2. The total area of the city is 212.41 square kilometres (82.01 sq mi).