John Packard Carter, 52, director of government relations for the Control Data Corporation here and a former official of the Post Office Department, died of an abdominal aneurysm Thursday at Arlington Hospital. He lived in Reston.

Mr. Carter, a former Texas businessman, came to Washington during the Johnson administration in 1964 to serve in various capacities at the Post Office Department. He was executive assistant to the postmaster general and director of the office of regional administration when he resigned in 1967 to become executive director of the National Association of Postmasters. He joined Control Data in 1971.

He was born in Smithville, Tex., and was a graduate of Schreiner Institute in Kerrville, Tex., and North Texas State College. After a tour of duty with the U.S. Air Force, he became a research technician at Dow Chemical in Freeport, Tex., and then was general superintendent of Blackmon and Associates at Mineral Wells, Tex., before coming here.

Mr. Carter was a member of Rockville Lodge 2296 of the Elks, the International Club of Washington and the National Democratic Club. A master Mason, he belonged to Benjamin B. French Lodge no. 15. He was a member of the Goose Creek Country Club.

His wife, the former Floy Louise Byram (Louise Carter), died a year ago.

Survivors include a daughter, Charlene Kenjura of Hallettsville, Tex.; two sons, Clifton and David, both of Falls Church, and two grandchildren.

The family suggests that expressions of sympathy be in the form of contributions to the Smithville Library in Smithville, Tex.