Francis X. Porrino, 46, a National Security Agency official who was active in church affairs, died Sunday at the Greater Laurel-Beltsville Hospital in Laurel after a heart attack.

He joined the agency in 1955, and served both here and overseas. For the past two years he had been chief of the office of operations.

Mr. Porrino helped build St. Nicholas Catholic Church in Laurel several years ago, and since that time had been an usher and lector.

He was a native of Philadelphia. He was a graduate of both the University of Maryland and the National War College.

He werved with Air Force security in Korea during the conflict there.

Mr. Porrino was president of the Communications Analysis Association, a professional society, at the time of his death.

He was given the Civilian Meritorious Service Award in 1964.

He is survived by his wife, Angela Dea, two daughters, Regina and Cara, and a son, James, all of the home in Laurel; another son, Stephen, of Laurel; a brother, Alfred (Bul), of Lafayette Hill, Pa., and two sisters, anita diLrenzo and Marie Hedrick, both of Philadelphia.

The family suggests that expressions of sympathy be in the form of contributions to the national Heart Fund.