John Duncan MacFarlane (July 27, 1892 – December 8, 1982) was a Scottish-born farmer and political figure in Saskatchewan. He represented Melfort from 1934 to 1938 as a Liberal. He was born in Gargunnock and was educated in Scotland. He later worked for a law office in Stirling. In 1910, MacFarlane came to Canada, where he worked on farms and eventually earned his engineer's certificate. He graduated from the University of Saskatchewan in agriculture. MacFarlane served with the Royal Canadian Engineers and then with the Royal Flying Corps during World War I. After the war, he worked for the Soldier Settlement Board for three years. MacFarlane then settled on a farm near Carlea, Saskatchewan, where he raised Clydesdale horses, Shorthorn cattle, Yorkshire pigs, Shropshire sheep and Barred Ro