Virginia Fox Hartley, 74, a retired special assistant in the State Department's Bureau of International Organization Affairs, died Jan. 18 at Georgetown University Hospital following a heart attack. She lived in Washington.

Mrs. Hartley joined the State Department in 1941 and worked on plans for what became the United Nations. She was a State Department adviser at the Dumbarton Oaks Conference, a meeting that led to the establishment of the UN, and the organization's charter conference in San Francisco.

After World War II, she left State for a year to help compile the authorized biography of Cordell Hull, the department's secretary from 1933 to 1944.

She returned to the State Department in 1947, where she was a special assistant in the international organization affairs bureau until retiring in 1977.

Mrs. Hartley was a native of Montana. She earned bachelor's and master's degrees at Stanford University and studied in Paris before moving to Washington in 1931. She was a research assistant at the Library of Congress and worked for the National Resources Planning Board before joining the State Department.

She was the widow of Robert W. Hartley, a former vice president of the Brookings Institution, who died in 1971. Mrs. Hartley leaves no immediate survivors.