| Birthname: | Jacob Pitzer Cowan |
| Jacob P. Cowan | |
| State: | Ohio |
| Term Start: | March 4, 1875 |
| Term End: | March 3, 1877 |
| Preceded: | John Berry |
| Succeeded: | Ebenezer B. Finley |
| Party: | Democratic |
| Birth Date: | 20 March 1823 |
| Birth Place: | Washington County, Pennsylvania, US |
| Death Place: | Ashland, Ohio, US |
| Restingplace: | Ashland Cemetery |
| Alma Mater: | Starling Medical College |
Jacob Pitzer Cowan (March 20, 1823 – July 9, 1895) was an American physician and politician who served one term as a U.S. Representative from Ohio from 1875 to 1877.
Born in Florence, Washington County, Pennsylvania Cowan attended the common schools.He moved with his parents to Steubenville, Ohio, in 1835.He engaged in the manufacture of woolens until 1843.He studied medicine.
In 1846 moved to Ashland County, Ohio, where he commenced the practice of his profession.He was graduated from Starling Medical College, Columbus, Ohio, March 6, 1855.
He served as member of the State house of representatives 1855-1857.He resumed the practice of medicine in 1859.
Cowan was elected as a Democrat to the Forty-fourth Congress (March 4, 1875 – March 3, 1877).He served as chairman of the Committee on Militia (Forty-fourth Congress).He was an unsuccessful candidate for renomination in 1876.
He again engaged in the practice of medicine in Ashland, Ohio, where he died July 9, 1895.
He was interred in Ashland Cemetery.