Harvey Reginald MacMillan, CC CBE (September 9, 1885 – February 9, 1976) was a Canadian forester, forestry industrialist, wartime administrator, and philanthropist.

Born in Pine Orchard, Whitchurch Township, Ontario (today part of Whitchurch–Stouffville), he attended school in Bogarttown, Sharon, and Aurora.

[1] He graduated from the Ontario Agricultural College[2] (then part of the University of Toronto) in 1906 with an honours degree in biology.

[2] In 1919, backed by British timber merchant Montague Meyer, MacMillan established the H.R.

MacMillan Export Company, Ltd.[2] He was Honorary Colonel of the Seaforth Highlanders of Canada from November 23, 1953, to August 7, 1957.