Last name Ōishi (大石 
, Ōishi) , in the world, is a rare cognomen. The family name Ōishi is habitual in Eastern Asia, particularly China, where it is a very rare surname. More frequently, Ōishi is the forename as well as the last name.
| ōishi sadahisa retainer of the Ogigayatsu-Uesugi branch of the Uesugi, and the builder of Takiyama Castle (b. 1491) |
|
|
| ōishi yoshikatsu samurai (b. 1587) |
|
|
| ōishi nobukoto samurai (b. 1592) |
|
|
| ōishi yoshitaka samurai; grandfather of Ōishi Yoshio (b. 1618) |
|
|
| ōishi yoshishige samurai (b. 1619) |
|
|
| ōishi mujin samurai (b. 1627) |
|
|
| ōishi yoshitsugi samurai (b. 1628) |
|
|
| ōishi nobuzumi samurai (b. 1636) |
|
|
| ōishi yoshiaki samurai; father of Ōishi Yoshio (b. 1640) |
|
|
| ōishi yoshifusa yonger brother of Ōishi Yoshio (b. 1671) |
|
|
| ōishi nobuoki samurai (b. 1674) |
|
|
| ōishi nobukiyo samurai; one of 47 ronin (b. 1677) |
|
|
| ōishi daizaburō son of Ōishi Yoshio (b. 1702) |
|
|
|
ōishi kumakichi (b. 1864) |
|
| ōishi yohei (b. 1854) |
|