David Samuel Horne MacDonald PC (born August 20, 1936) is a Canadian United Church of Canada minister, former politician, and author.

Born in Charlottetown, Prince Edward Island, David MacDonald was ordained in the United Church by the Maritime Conference on June 11, 1961, and was a minister at Alberton, Tignish, and Cascumpec, Prince Edward Island before going into federal politics.

He ran as the NDP candidate in his old riding (now called Toronto Centre-Rosedale) in the 1997 election, but was defeated again by Graham.

On November 25, 1998, The United Church of Canada appointed MacDonald a Special Advisor on residential schools, in light of major lawsuits against the UCC from former students.

MacDonald was romantically involved with Alexa McDonough who at the time was leader of the federal NDP, prior to his 1997 candidacy.