John G. Conkey III, 71, a lawyer who was a longtime government employe and retired official of the U.S. Maritime Administration, died of diverticulitis Tuesday at Suburban Hospital.

He began his government career as a claims officer with the State Department in 1929, then was an administrator with the old National Recovery Administration from 1933 to 1935. He then spent five years as a personnel and procurement officer with the Treasury Department.

He served with the Navy in the Pacific during World War II. Mr. Conkey then joined the Maritime Administration, where he was chief of purchase and sales, when he retired in 1968. Since that time he had practiced law in Chevy Chase.

He was a recipient of the Commerce Department's Silver Medal for Distinguished Service.

Mr. Conkey was a fourth-degree member of the Knights of Columbus and was a past-grand knight of the Columbus Lodge. He also was a member of the University Club and the Kenwood Golf and Country Club.

He was a native of Kansas City, Mo., and a graduate of George Washington University. He earned his law degree there in 1929.

Survivors include his wife, Pearl (Pat), of Chevy Chase; a son, John, of Laurel; a daughter, Carolyn Conkey of Silver Spring; two brothers, George, of Los Angeles, and Snowden, of Rockville, and two grandchildren.