Donald Greenfield MacDonell (July 2, 1849 – November 12, 1916) was a lawyer and political figure in Ontario, Canada.
He represented Lanark North in the House of Commons of Canada from 1880 to 1882 as a Liberal member.
He was educated at Upper Canada College in Toronto.
MacDonell was married twice: to Margaret Rosamond in 1875 and to Edith Rose in 1880.
MacDonell was first elected to the House of Commons in an 1880 by-election held after the death of Daniel Galbraith.