John L. Thompson, 68, a former business manager of the Washington Redskins football team and a retired owner and operator of the Colonial Awning Company of Falls Church, died Sunday at his home in Goose Creek, S.C., after a heart attack.

Mr. Thompson became affiliated with the Redskins in 1937 and was the team's business manager from the early 1940s to 1949, when he left to found Colonial Awning.

An Army veteran of World War II, he was a life-member and past-commander of the Unknown Soldier Post No. 44 of the American Legion in Arlington. He also had been 10th District Commander of the Legion. He was a member of the Lions Club and the Artisans in Arlington.

Mr. Thompson was a native of Dayton, Va., and a graduate of Shenandoah College. He lived in Washington and Arlington for 47 years before retiring in South Carolina in 1978.

Survivors include his wife, Ida, of Goose Creek; three daughters, Barbara Brown, of McLean, Brenda Manly, of Arlington, and Betsy Alexander of Ladson, S.C., and four grandchildren.

The family suggests that expressions of sympathy be in the form of contributions to the American Heart Association, or to the American Diabetes Association.