Charles O'Neill (March 21, 1821 - November 25, 1893) was a Republican member of the U.S. House of Representatives from Pennsylvania.
Charles O'Neill was born in Philadelphia, PA. He was graduated from Dickinson College in Carlisle, PA in 1840. He was a member of the Pennsylvania House of Representatives from 1850-1852 and again in 1860. He served in the Pennsylvania State Senate in 1853.
In 1862 he was elected as a Republican to the 38th and to the three succeeding Congresses (March 4, 1863-March 3, 1871). He was an unsuccessful candidate for reelection in 1870. He was again elected to the 43rd Congress and served from March 4, 1873 until his death.