William John McKeag, CM OM CD (17 March 1928 – 23 August 2007) was a Manitoba politician and office-holder.
He served as general manager of Security Storage Limited (a family business) from 1952 until his appointment in 1970.
In 1958, McKeag ran for the Manitoba legislature as a Liberal-Progressive candidate in the upscale Winnipeg riding of River Heights.
McKeag, at the age of 42, was the youngest lieutenant governor in Manitoba's history when he was appointed by Prime Minister Pierre Elliott Trudeau in 1970.
However, the office of lieutenant governor is a ceremonial post, and he had almost no practical influence over the government of Edward Schreyer.