Cargill MacMillan Sr. (October 10, 1900 - October 16, 1968) was an American business executive, serving as the President of Cargill in Minneapolis.
MacMillan was born on October 10, 1900. He was the second son of John H. MacMillan Sr. and Edna Clara Cargill.
MacMillan served as the President of Cargill.
He married Pauline Whitney (1900–1990), and they had four children. Each of the three surviving adult children received a one-ninth share of Cargill.
MacMillan died on October 16, 1968.