William Abbott Moseley (October 20, 1798 Whitesboro, Oneida County, New York – November 19, 1873 New York City) was an American physician, lawyer and politician from New York. He graduated from Yale College in 1816. Then he studied medicine and practiced as a physician. Then he studied law, was admitted to the bar, and practiced law in Buffalo, New York. He was a member of the New York State Assembly (Erie Co.) in 1835. He was a member of the New York State Senate (8th D.) from 1838 to 1841, sitting in the 61st, 62nd, 63rd and 64th New York State Legislatures. Moseley was elected as a Whig to the 28th and 29th United States Congresses, holding office from March 4, 1843, to March 3, 1847. Afterwards he resumed the practice of law. He was buried at the Forest Lawn Cemetery, Buffalo.