Janet Arcuni Hartle, 50, assistant director of the court interpreters program at the Administrative Office of the U.S. Courts since last December, died of cancer Wednesday at George Washington University Hospital.

She was on leave of absence from Antioch University in Yellow Springs, Ohio, where she had been director of Academic Affairs since 1976, working from offices here.

In 1975, Dr. Hartle was assistant executive secretary of the Presidential Clemency Board. In 1974-75, she was a consultant to the Justice Department's Law Enforcement Assistance Administration.

She was born in Long Beach, N.Y., graduated from Hunter College and earned a doctorate in anthropology from Columbia University.

Dr. Hartle was a lecturer in anthropology at Howard University in 1960-62. She then was head of the department of sociology and anthropology at the University of Nigeria in Nsukka for four years.

She returned to Washington to work with the Peace Corps as deputy director of research here and then as regional director for the Leeward Islands and chief of programs for the Caribbean, based in Antigua. She lived in Washington at the time of her death.

Her marriage to Donald Hartle ended in divorce.

She is survived by her mother, Rose K. Arcuni, of Alexandria, and a brother, Orestes K. Arcuni, of Triangle, Va.

The family suggests that expressions of sympathy be in the form of contributions to the American Cancer Society, or to the Arthritis Foundation.