Robert H. Carey, 38, a public relations official with the American Gas Association and a former congressional aide, died of pneumonia Saturday at Sibley Memorial Hospital. He lived in Silver Spring.

Mr. Carey was born in New York City and grew up in Highland Park, Ill. He attended Shimer and McMurray colleges in Illinois.

He moved to the Washington area in 1968 and joined the staff of Sen, Wayne Morse (D-Wash.). Mr. Carey later was press secretary to Rep. Charles Wilson (D-Calif.) and to Sen. Lloyd Bentsen (D-Tex.).

In the early 1970s, he was on the staff of the American Association of Retired Persons. For five years beginning about 1973, he was an advertising account executive with radio station WMAL-FM. He joined the American Gas Association last year.

Mr. Carey was active for many years in theatricals. In his student days, he was a finalist in a national dramatic competition, playing the role of Capt. Queeg in "The Caine Mutiny." In this area, he had performed with the Rockville Little Theater and other groups.

Survivors include his wife, V. Marie Bass, and a son, Timothy, of Silver Spring; his mother, Virginia Morris Carey of Prescott, Ariz.; two sisters, Jocelyn Gordon of Aptos, Calif., and Nancy Carey of Brentwood, Calif., and one brother, William Carey of Pacific Palisades, Calif.

The family suggests that expressions of sympathy be in the form of contributions to the D.C. Lung Association.