Florence Deller Conroy, 58, an Arlington County recreation leader who also had taught piano, died Wednesday at her home in Arlington after apparently suffering a heart attack.

As a part-time recreation leader, she had taught bridge and cooking for the last five years. Her classes were known as "Flo's Bridge" and "Dollar-Stretcher" cooking.

Mrs. Conroy gave private piano lessons from 1966 to 1974. She had lived in the Washington area off and on since 1956, and settled here in 1966.

The wife of a retired Foreign Service officer, John H. Conroy, she had accompanied him on tours of duty to Dacca, Pakistan, Tehran, Iran, and Tunis, Tunisia, between 1956 and 1966 and had been active with the Foreign Service Wives in those countries.

Mrs. Conroy was born in Cambria, Okla... She received a bachelor's degree in music from Oklahoma Women's College and later attended Virginia Polytechnic Institute. She was a court reporter in McAllister, Okla., a secretary at Borden General Hospital in Chickasha, Okla., and taught piano in Westbury, N.Y.

From 1952 to 1956, she taught music and was an administrator at Antilles School, St. Thomas, Virgin Islands, while her husband was there for the U.S. Agriculture Department.

In addition to her husband, she is survived by a son, John H., and a daughter, Alison A., all of the home; another daughter, Linda Thornley, of Maplewood, N.J.; two brothers, Frank Deller, of Knoxville, Tenn., and John R. Deller, of Oklahoma, and three grandchildren. CAPTION: Picture, FLORENCE D. CONROY