Rudy G. Larson, 65, a retired director of government relations for the Addressograph Multigraph Corp. in Washington, died at Suburban Hospital in Bethesda on Sunday of cardiac arrest and arteriosclerotic heart disease.

Mr. Larson was born in Minneapolis, and grew up there and in Robbinsdale, Minn. He joined the Addressograph Multigraph Corp. in Chicago in 1937.

He came to Washington about 1946 as the company's branch sales manager here. He served as branch manager, director of government marketing and director of government relations until his retirement in 1972.

Mr. Larson then became a vice president of the Andrews Office Supply Co. in Washington, a position he held until he retired a second time in 1975.

During World War II, Mr. Larson enlisted in the old Army Air Corps as a private. He held the rank of captain when he left the service.

He was an elder of the Bradley Hills Presbyterian Church in Bethesda. He also was a founding member of Heroes, Inc., a past president of the Washington Office Equipment Managers Association, the Bradley Boulevard Citizens Association in Bethesda and the Seaside Village Civic Association in Bethany Beach, Del., and a member of the University, Kenwood Country and Host Lions clubs and the Circus Saints and Sinners.

Mr. Larson was a Mason and a past potentate of the Almas Temple, and member of the Scottish and York Rite Bodies, a past master of the Bethesda Lodge No. 204 and a member of other Masonic groups.

Survivors include his wife, Aileen, of the homes in Bethesda and Bethany Beach, and a sister, Alice Ehrich, of Cortez, Fla.

The family suggests that expressions of sympathy be in the form of contributions to the Shriners Hospital for Crippled Children, c/o The Almas Temple, 1315 K St. NW. CAPTION: Picture, RUDY G. LARSON