L. Marguerite Bulkley, 67, a Washington resident for 36 years who was active in efforts to legalize heroin for the treatment of pain in cases of terminal illness, died Monday at Montgomery General Hospital. She had cancer.

At the time of her death, Mrs. Bulkley lived in Silver Spring and was an active member of "Make Today Count," a support group for terminally ill persons and their families, and the National Committee on the Treatment of Intractable Pain.

The committee, an educational, research and promotional group founded here in the mid-1970s by Judith H. Quattlebaum of Potomac, has been involved in lobbying efforts for passage of bills introduced by Rep. Edward R. Madigan (R-Ill.) and Rep. Henry A. Waxman (D-Calif.) to legalize the use of heroin for the terminally ill and for cancer patients.

Mrs. Bulkley recently appeared in a segment of a television news program on these issues produced by Metromedia Inc. and telecast here and in New York City.

A native of Ornskoldsvik, Sweden, she came to this country with her family as a child and grew up in New Britain, Conn. For the last 11 years, she was a member of Rossmoor Leisure World's Interfaith Chapel and its Music Lovers Club.

Her husband, Bernard Bulkley, a Silver Spring businessman, died last year.

Survivors include a daughter, Deborah Tippit of Olney; a son, Stephen, of Seattle, and a brother, Raymond Peterson of Newington, Conn.

The family suggests that expressions of sympathy be in the form of contributions to the Montgomery County Unit of the American Cancer Society for the Make Today Count Program, or to the Salvation Army.