| Honinbo Josaku | |
| Fullname: | Honinbo Josaku |
| Birth Date: | 1801 |
| Birth Place: | Japan |
| Death Date: | 1847 |
| Death Place: | Japan |
Hon'inbō Jōsaku (本因坊丈策, 1803–1847) was a Japanese professional go player and the thirteenth head of the Hon'inbō school.[1] He was not in the same top-rank class over the board as either his predecessor Jōwa or his successor Shūwa.[2]