Margery Jean Beazley Donnelly, 52, a former chairperson of the Fairfax County Commission for Women who had been active in the women's movement in Virginia since the mid-1970s, died of cancer Monday at Fairfax Hospital.

She was a member of the Human Resources Citizen's Advisory Committee of the Metropolitan Council of Governments and the National Women's Political Caucus.

Mrs Donnelly had served on the Fairfax County Commission for Women since 1976. She was the commission's vice chairperson in 1976-7 and chairperson from 1977-8.

Esther Ochsman, the commission's director, said that Mrs. Donnelly was instrumental in starting the Fairfax County Women's Shelter, a facility for battered women, in October 1977. Mrs. Donnelly also helped work for the creation of a Fairfax County employment center for women and served on the Commission's Women's Court Observer Program.

As a member of both the Virginia State Crime Commission Task Force on Criminal Assault and the Virginia Coalition on Sexual Assault Reform since 1976, she had advocated reform of state rape laws.

According to Ochsman, Mrs. Donnelly had worked for a comprehensive code on sexual crimes that would put greater emphasis on rape as a crime of violence and would tie sentencing of convicted rapists to the degree of violence they had used.

In 1978, the Fairfax County Board of Supervisors gave its Human Rights Award to the Fairfax County Commission for Women. The commission then presented the award to the Donnelly family "as a symbol of Marge's enormous contribution" to the commission's work.

Mrs. Donnelly carried on her work despite the fact that she had had cancer since 1972.

She had lived in Fairfax County since 1966. In 1973, she entered George Washington University to study toward a master's degree in women's studies. During the next two years she twice was hospitalized with cancer. She earned her degree in 1977.

While at GW, she also was a member of the Student Advisory Board of the women's studies program and a graduate assistant.

She developed cancer of the hip in January 1977 and underwent treatment for that while continuing to attend hearings and conferences on women's rights in Northern Virginia. In November 1978 the cancer spread to the brain stem, but Mrs. Donnelly continued to champion her causes until mid-March, when she was forced to retire.

Mrs. Donnelly was a native of Charleston, W.Va., and a 1949 cum laude graduate of Ohio State University where she earned a bachelor's degree in English and was elected Phi Beta Kappa.

In addition to her work with women's groups, she had been president of the Camelot Garden Club in 1969-70, and assistant area director for Virginia of the National Capital Area Federation of Garden Clubs during the early 1970s.

Survivors include her husband, William F. Donnelly, a son, John Mark, and a daughter, Elizabeth Jane, all of the home in Annandale, and a sister, Frances Curry, of Madison, W.Va.

The family suggests that expressions of sympathy be in the form of contributions to the Fairfax County Commission for Women -- Reentry Women's Employment Center, or to the American Cancer Society.