 Tilleman was born and raised on a ranch near Zurich, Montana by Henry (Hank) and Irma Tilleman (née D'Hooge), where he went to school in a one room schoolhouse.He was a prep star at Chinook High School and attended the University of Montana on scholarship.Tilleman played for the Grizzlies from 1963 to 1964, where he was a second team All-Big Sky Conference selection in both seasons.