Luke Andrew Johnsos, Sr. (December 9, 1905 - December 10, 1984) was an American football player, assistant coach, and head coach for the National Football League's Chicago Bears franchise. He started with the Bears in 1929 at the age of 23 as an All-Pro end. He played eight NFL seasons in Chicago finishing his playing career in 1936. Following the October 25, 1942 victory over the Philadelphia Eagles, Chicago's twelfth victory in a row, George Halas turned his team over to assistants Hunk Anderson and Luke Johnsos.
Johnsos graduated from Schurz High School in Chicago, Illinois in 1924, while there he played football and baseball. After graduation he went to Northwestern University and lettered in basketball, baseball, and football - 9 letters total.