James Hugh Relfe (October 17, 1791 – September 14, 1863) was a U.S. Representative from Missouri.

Born in Virginia, Relfe moved to Washington County, Missouri, about 1816 with his father, who settled in Caledonia. He received a limited schooling. He studied medicine and practiced in Caledonia, Missouri. He was appointed a member of the commission to adjust Spanish land claims to fill the vacancy occasioned by the resignation of his brother-in-law, Dr. Lewis F. Linn. He served as member of the State house of representatives 1835-1844. He served in the Black Hawk War. He was appointed United States marshal for the district of Missouri February 17, 1841.

Relfe was elected as a Democrat to the Twenty-eighth and Twenty-ninth Congresses (March 4, 1843 – March 3, 1847). He continued the practice of medicine in Caledonia, Washington County, Missouri, until his death there September 14, 1863. He was interred in the Methodist Cemetery.

• United States Congress. "James H. Relfe (id: R000160)". Biographical Directory of the United States Congress.

• James H. Relfe at Find a Grave