Mary Ann Silver, 64, retired head of the permit control division of the old D.C. Department of Motor Vehicles, died of cancer Saturday at Arlington Hospital.

Once described as a "real-life example of a government girl who made good," Mrs. Silver had held one of the more powerful jobs in the city government. She retired in 1972 after more than 30 years of service.

She had started in 1941 as a temporary worker during an auto tag rush and a year later received a civil service appointment as financial responsibility clerk in what was then the D.C. Department of Vehicles and Traffic.

In 1946, Mrs. Silver was appointed the first woman head and secretary of the old board of revocations and restoration of operators' permits. She also was named head of the hackers' appeals board, a position she held until 1970.

When the department was streamlined in 1956, she was named head of the permit control division. Driver examination and permit issuance, driver records and driver improvement were brought under her jurisdiction.

During her tenure, Mrs. Silver was often heavily criticized, particularly by those who lost their licenses. From the other side, she was often lavishly praised. At the time of her retirement, she said she was always proud that no one had accused her of being unfair.

Born in Washington, she was a graduate of old Business High School.

Mrs. Silver, who lived in Arlington, later devoted most of her time to working with the Ladies Auxillary of Arlington Hospital. She served as its president in 1973-74. She also was coordinator of and general adviser to the hospital's gift shop.

She is survived by a brother, Chares B. Tyson Jr., of Annandale.