Moses Macdonald (April 8, 1815 – October 18, 1869) was a United States Representative from Maine. He was born in Limerick, Maine, where he received an academic education. Later, he studied law, was admitted to the bar in 1837, and commenced practice in Biddeford, Maine in 1837.
Macdonald was a member of the Maine House of Representatives in 1841, 1842, and 1845. He served as Speaker of the Maine House of Representatives in 1845. Later, he served in the Maine Senate in 1847 and was the Maine treasurer 1847-1850.
Macdonald was elected as a Democrat to the Thirty-second and Thirty-third Congresses (March 4, 1851-March 3, 1855). In Congress, he served as chairman, Committee on Revolutionary Claims (Thirty-second Congress). He was appointed collector of customs at Portland, Maine by President James Buchanan in 1857 and served until 1861. He died in Saco, Maine in 1869 and was buried in Laurel Hill Cemetery.