| Thomas Ash Tomlinson | |
| State: | New York |
| District: | 13th |
| Term Start: | March 4, 1841 |
| Term End: | March 3, 1843 |
| Preceded: | Augustus C. Hand |
| Succeeded: | Daniel D. Barnard |
| Office2: | Member of the New York State Assembly |
| Term Start2: | 1835 |
| Term End2: | 1836 |
| Birth Date: | March 1802 |
| Birth Place: | New York City, U.S. |
| Death Place: | Keeseville, New York, U.S. |
| Party: | Whig |
Thomas Ash Tomlinson (March 1802June 18, 1872) was a U.S. Representative from New York.
Born in New York City in March 1802, Tomlinson attended the schools of Champlain and Plattsburgh, New York. He studied law and gained admission to the bar, commencing practice in Keeseville, New York, in 1823. He was a mill owner and dealer in lands, serving as a colonel in the state militia and as a member of the New York State Assembly in 1835 and 1836.
Tomlinson was elected as a Whig to the Twenty-seventh Congress (March 4, 1841 – March 3, 1843). He thereafter resumed the practice of law and also engaged in the real estate business. He died in Keeseville, New York, June 18, 1872, and was interred in Evergreen Cemetery.