Benedict Joseph Semmes (November 1, 1789 – February 10, 1863) was an American politician.
Born in Charles County, Maryland, Semmes attended the rural schools and a medical college in Philadelphia.
He graduated from Baltimore Medical School in 1811 and commenced practice in Prince George's County, Maryland.
He served in the Maryland State Senate, and was elected as an Anti-Jacksonian to the Twenty-first and Twenty-second Congresses, serving from March 4, 1829, to March 3, 1833.
He lived in retirement until his death at Oak Lawn in Prince George's County.