Mary Colvin Murphy, 92, a retired analyst for the National Security Agency who was active in Episcopal church affairs and patriotic groups, died Monday at the Rockville Nursing Home after a stroke.

A Washington area resident since 1943, Mrs. Murphy worked in the House Office Building for a number of years before transferring to the National Security Agency after it was established in 1952. She was an analyst when she retired in 1963.

She was born in Atkinson, N.C., and attended Peace College in Raleigh, N.C. In 1912, she married Dr. William Bailey Murphy of Snow Hill, N.C. He died in 1937.

Mrs. Murphy, who had been active in church work in Snow Hill, was a member of the National Presbyterian Church in Washington. She also was a member of the Al Hallows Guild of Washington Cathedral and was a former volunteer for the St. Alban's Church Opportunity Shop.

She was active in the National Society of Colonial Dames of America, the Club of Colonial Dames in Washington, the Daughters of the American Revolution and the United Daughters of the Confederacy.

Mrs. Murphy lived in Washington until March, when she moved to the Rockville Nursing Home.

Survivors include a daughter, Mrs. James A. Griffin, and two granddaughters, all of Bethesda.