John Grant McKenzie (1882–1963) was a Scottish Congregational minister, psychologist and academic.

McKenzie was born in Aberdeen on 5 February 1882[1] and studied at the University of Aberdeen,[2] winning the Dor Williams Divinity Scholarship in 1910.

[1] In 1921, McKenzie was appointed the first Jesse Boot Professor of Sociology and Psychology at Paton Congregational College in Nottingham.

[1] According to his obituary in The Times, he was "a pioneer in the relationship of psychology and religion ... [who] helped many generations of theological students to understand the workings of the human mind".

He had married Margaret Ann Murray in 1912 and had a son, the comedian Michael Howard, and a daughter,[2] Dr Margaret Ross, who married Dr Frederic Laws and was mother to the judge Sir John Grant McKenzie Laws.