John McDonald Mowat (February 17, 1872 – October 7, 1916) was a lawyer and politician in Ontario, Canada.

Mowat practised law in Kingston and later in Vancouver, British Columbia.

[2] He ran unsuccessfully for the Kingston seat in the Canadian House of Commons in 1911, losing to William Folger Nickle.

[3] He went overseas as a Major with a Vancouver regiment during World War I and was killed in action at the age of 44.

[1] His nephew Angus McGill Mowat also served in World War I, and his great-nephew is Canadian author Farley Mowat.