Karen Louise Lyman, 30, a former student at George Mason University, where she worked in the career counseling office, died of cancer Sunday at the Emerson Hospital in Concord, Mass.

Mrs. Lyman was born into a military family at Bolling Air Force Base in Washington. She grew up at various military posts in the United States and in Australia, Japan and France.

She graduated from Florida Junior College in Jacksonville and attended the University of Florida at Gainesville. She moved to the Washington area in 1975 and was a resident of Alexandria until last month, when she moved to Acton, Mass.

Before working and studying at George Mason, she worked for an electronics firm in Alexandria and for other businesses.

Her marriage to Francis Morris ended in divorce and Mrs.Lyman resumed use of her maiden name.

Survivors include her son, Trevor Morris Lyman of Acton; her mother and stepfather, Dorothy L. and Victor O. McNabb of Falls Church; three brothers, Edwrd M. Lyman Jr. of Roselle, Ill., Carter S. Lyman of Acton, and Steven G. Lyman of Atlanta.

The family suggest that expressions of sympathy be in the form of contributions to the American Cancer Society or to the St.James Episcopal Church Memorial Garden Fund, Mount Vernon.