| James O'Hanlan Patterson | |
| State: | South Carolina |
| Term Start1: | March 4, 1905 |
| Term End1: | March 3, 1911 |
| Predecessor1: | Theodore G. Croft |
| Successor1: | James F. Byrnes |
| Office2: | Member of the South Carolina House of Representatives from Barnwell County |
| Term Start2: | January 10, 1899 |
| Term End2: | February 20, 1904 |
| Birth Date: | 25 June 1857 |
| Birth Place: | Barnwell, South Carolina |
| Death Place: | Barnwell, South Carolina |
| Resting Place: | Orangeburg, South Carolina |
| Party: | Democratic |
| Profession: | attorney |
James O'Hanlon Patterson (June 25, 1857 – October 25, 1911) was a United States representative from South Carolina.
He was born in Barnwell, South Carolina. He attended private schools in town and also in Augusta, Georgia. Later, he studied law, was admitted to the bar in 1886, and commenced practice in Barnwell, South Carolina.
Patterson was a probate judge of Barnwell County, South Carolina 1888–1892 and a member of the South Carolina House of Representatives 1899–1904. He was elected as a Democrat to the Fifty-ninth, Sixtieth, and Sixty-first Congresses (March 4, 1905 – March 3, 1911). After leaving Congress, he resumed the practice of his profession in Barnwell, South Carolina where he died on October 25, 1911. He was buried in the Episcopal Cemetery.