Rosemarie Becker, 53, a retired real estate agent in Columbia who was active in community affairs and youth groups, died of cancer Wednesday at the Howard County General Hospital in Columbia.

Mrs. Becker was born and reared in New York City. She came to this area in 1949 with her husband, Eugene J. Becker, a civilian employe of the Department of Defense.

In the 1950s, Mrs. Becker was a legal secretary in the civil division at the Department of Justice. She then worked at the University of Maryand's counseling center and, for the past few years, worked as real estate agent for Monarch Realty in Columbia. She retired last summer for reasons of health.

From 1972 to 1975, Mrs. Becker lived in Turkey, where her husband was on assignment for the Defense Department. While there she conducted English classes for Turkish women.

Mrs. Becker was active for many years in Democratic politics in Prince George's County and was a member of the League of Women Voters. She worked as a volunteer with youth clubs in New Carrollton and with local civil rights groups in the 1960s.

She also was a member of the Turkish-American Association.

Besides her husband, of the home in Columbia, survivors include three children, David and Nancy, of the home, and Carol Bowie, of Falls Church, and one grandson.