| John Curtin | |
| Birth Date: | 15 May 1867 |
| Birth Place: | Gold Springs, California, U.S. |
| Death Place: | Sonora, California, U.S. |
| State Senate: | California |
| District: | 12th |
| Term Start: | January 2, 1899 |
| Term End: | January 4, 1915 |
| Preceded: | John Henry Shine |
| Succeeded: | Lafayette Jackson Maddux |
| Office1: | District Attorney of Tuolumne County |
| Term Start1: | 1892 |
| Term End1: | 1898 |
| Party: | Democratic |
| Spouse: | Lucy A. Shaw |
| Children: | 1 |
| Occupation: | Attorney |
John Barry Curtin (May 15, 1867 – May 18, 1925) was an American attorney and politician who served in the California State Senate representing the 12th district from 1899 to 1915.[1] In 1914, he was the Democratic nominee for Governor of California, but lost to incumbent Hiram Johnson.