John Duncan Stewart (October 16, 1859 – 1921[1]) was a farmer and political figure in Saskatchewan.
He represented Cannington in the Legislative Assembly of Saskatchewan from 1905 to 1921 as a Liberal.
He was born in Perth County, Canada West, and was educated there.
[2] Stewart received homestead land in Saskatchewan in 1882.
Stewart ran unsuccessfully for a seat on the Legislative Assembly of the North-West Territories in 1902.