Charles L. Spettel, 55, a retired Army colonel who had taught mathematics at Stuart High School in Fall Church since 1974, died of cancer Wednesday at Walter Reed Army Hospital.

Col. Spettel enlisted in the Army during World War II. He later entered the U.S. Military Academy at West Point, graduating with the class of 1949. During his 26-year Army career, he was an armored officer in peacetime Europe, a math instructor at West Point and a member of the staff of the Army's Office of Personnel Operations in Washington.

In addition to Europe, he held assignments in Israel, Australia and Korea. He was a staff officer in Viet nam in the late 1960s. Col. Spettel was stationed at the Army's Combat Development Command at Fort Belvoir at the time he retired in 1974.

He was a graduate of the Army's Command and General Staff College, the Armed Forces Staff College, and had earned a master's degree in math- ematics at Columbia University. His Army decorations included the Legion of Merit and the Bronze Star Medal.

Col Spettel was born in Fort Snelling, Minn. He was a resident of Alexandria. He was a sailing enthusiast who had won a number of trophies and was a member of the Mt. Vernon Yacht Club.

Survivors include his wife of 31 years, the former Ebba Jo Tate, of Alexandria; two sons, Scott, of Chapel Hill, N.C., and Stewart, of Alexandria; two daughters, Nancy Stamm, of Crozet, Va., and Martha Spettel, of Alexandria; two brothers, Frank, of Columbus, Ga., and Thom, of Boston; a sister, Ann Ware, of Alexandria, and one grandchild.

The family suggests that expressions of sympathy be in the form of contributions to the National Symphony Orchestra or the Christian Children's Fund in Richmond.