Stewart Hoffman Appleby (May 17, 1890 – January 12, 1964) was an American businessman, military officer, and politician who served one term as a Republican Party politician who represented New Jersey's 3rd congressional district from 1925–1927, filling the vacancy of his father T. Frank Appleby, who had been elected to office but died before taking the seat.

He graduated from Rutgers University, New Brunswick, New Jersey, in 1913 and afterward engaged in the real estate and insurance business.

Appleby organized and served as vice president of the First National Bank of Avon-by-the-Sea, New Jersey.

During the First World War, he enlisted in the United States Marine Corps on May 17, 1917, and served until May 17, 1921.

During World War II, Appleby served in the United States Coast Guard, being discharged in September 1945 as a coxswain.