| Hosai Fujisawa | |
| Fullname: | Hosai Fujisawa |
| Kanji: | 藤沢朋斎 |
| Birth Date: | March 5, 1919 |
| Birth Place: | Yokohama, Japan |
| Death Place: | Japan |
| Teacher: | Honinbō Shūsai |
| Rank: | 9 dan |
was a professional Go player. Hideyuki Fujisawa is his uncle.
Hosai Fujisawa was born in Yokohama, Japan. He was among the best players of the 20th century. He became an insei at the Nihon Ki-in when he was 11 years old. He became one of Honinbō Shūsai's disciples. He was known for a strong sense of will, reading deeply and taking long turns. He had a fuseki that was different from other players. Fujisawa would usually open the game on the 3-3 point in one of the corners, then make enclosures on the parallel corner when he played black. When he played white he often played imitation go.
In 1939 and 1940, Fujisawa played a Jubango against Go Seigen when they were respectively 6p and 8p. Fujisawa won the 10.match series 6 to 4, though he did benefit from josen handicap throughout.
He was the first player to be promoted to 9 dan in the Oteai system when he won the Oteai seven times. He was known for playing two jubango matches with Go Seigen some 10 years after the first jubango. These matches occurred in 1951 and 1952, the time when Fujisawa and Go were the only 9 dans. Fujisawa lost both of the matches.
| Title | Years Held | |
|---|---|---|
| Current | 2 | |
 Judan | 1964 | |
| Oza | 1958 | |
| Defunct | 1 | |
| Hayago Championship | 1971 |
| Title | Years Lost | |
|---|---|---|
| Current | 9 | |
| Honinbō | 1957 | |
| Judan | 1965, 1967 | |
| Oza | 1963 | |
| NHK Cup | 1955, 1957, 1960, 1967, 1969 | |
| Defunct | 3 | |
| Hayago Championship | 1968, 1970, 1972 |