Dr. Ping-Nie Pao, 59, the director of psychotherapy of Chestnut Lodge, a private psychiatraic hospital in Rockville, died Thursday at George Washington University Hospital. He had cancer.

Dr. Pao was born in Shanghai, China, and earned his medical degree at the National Medical College of Shanghai. He came to the United States in 1948 and received his psychiatric training at the Sheppard and Enoch Pratt Hospital in Towson, Md. He was trained in psychoanalysis at the Washington Psychoanalytic Institute.

Dr. Pao, who lived in Bethesda, joined the staff of Chestnut Lodge in 1957. He was named director of psychotherapy in 1967 and held that position until his death. He also conducted a private practice at the hospital and at his office in Bethesda.

He was the author of numerous papers published in professional journals and wrote one book, "Schizophrenic Disorders," which appeared in 1979. In addition, Dr. Pao was a teaching analyst at the Washington Psychoanalytic Institute and lectured widely in this country and abroad on the theory and treatment of illness.

He was a member of the American Psychiatric Association, the American Psychoanalytic Society and the D.C. Medical Society.

Dr. Pao's wife, Dr. Pearl Shen, died earlier this year.

Survivors include one daughter, Maryland Pao, and one son, William Pao, both of Bethesda, and one brother in Shanghai.