Miriam McCottry Bell, 63, a retired D.C. public school aide and a former federal government employe, died Thursday at Washington Hospital Center. She had a heart ailment.

Mrs. Bell began her federal career about 1940 as a verifier with the Bureau of the Census. In the mid-1940s, she transferred to the Bureau of Engraving and Printing. Before leaving government service in the early 1960s, she worked for the Department of Health, Education and Welfare for several years.

About 1967, she joined the pupil personnel division of the D.C. puplic schools, where she remained until her retirement in 1978.

A native of Savannah, Ga., Mrs. Bell moved here with her family at an early age. She attended Shaw Junior High School and earned a certificate from Howard University's school of dental hygiene in 1937.

She was a longtime member of the Woodbridge Green Thumb Garden Club and won a number of ribbons for her exhibits at flower shows held at the U.S. Botanic Gardens here.

Mrs. Bell raised money for the kitchen fund of the 15th Street Presbyterian Church here by teaching cooking classes at the church. She was a former Sunday school secretary and chancel guild president at the church.

Survivors include her husband, Andrew J., of Washington; a son, Dr. Michael M., of Chicago; three daughters, Deidra B. Spann of Washington, Andrea Scott of Philadelphia, and Robin Washington of Hyattsville; her mother, Anna F. McCottry, a sister, Gwendolyn M. Miller, and two brothers, Dr. Samuel B. McCottry Jr., and James, all of Washington; another brother, Wilbur W., of Suitland, and a grandson.

The family suggests that expressions of sympathy be in the form of contributions to the 15th Street Presbyterian Church Kitchen Fund or to the United Negro College Fund in Care of the Church.