Charles R. (Dick) Wilson, 70, a retired branch chief of the Office of Naval Intelligence's Naval Investigative Service, died Tuesday at his home in Kilmarnock, Va., after a heart attack.

Mr. Wilson was head of the investigation branch of the Naval Investigative Service from 1946 until retiring in 1966. During those years, he directed security checks on personnel and also was in charge of Navy countersabotage and counterespionage operations.

He was a native of Washington and a graduate of the old Central High School. He earned a law degree at George Washington University and a graduate law degree there a year later.

From 1934 to 1938, he worked for the Federal Bureau of investigation, part of the time as night secretary to director J. Edgar Hoover. He then practiced law in Washington and Virginia for a year before receiving a Navy commission.

Mr. Wilson served with the ONI for six years on active duty, retiring in 1946 with the rank of commander. He stayed with ONI in a civilian capacity.

He had belonged to Damascus Lodge No. 16 in Washington and then Henry Lodge No. 41 in Fairfax of the Masons. Mr. Wilson retired to Kilmarnock in 1967.

His first wife, the former Minna Vivian Cannon, died in 1963.

Mr. Wilson's survivors include his wife of 10 years, the former Elizabeth Pickup McDowell, of Kilmarnock; two daughters, Minna Hall of Oklahoma City, and Mary Louise Bowen of Charlotte, N.C.; two sons, Richard C., of Winston-Salem, N.C., and John C., of Kilmarnock; a stepson, Ron McDowell of Ottawa, Canada, and 11 grandchildren.