Dr. David Shakow, 80, a psychologist who pioneered in the study of schizophrenia and who had served as scientist emeritus at the National Institute of Mental Health in Bethesda since 1968, died Thursday at Sibley Memorial Hospital. He had a heart ailment.

Dr. Shakow had served as chief of the clinical, developmental and experimental psychology laboratory at the institute since 1954. From 1966 until shortly before his death, he was senior research psychologist at the Institute.

One of Dr. Shakow's primary goals was to develop a theory of schizophrenia. In the early 1970s, he and his associates conducted one of the most complex multidisciplinary research programs in schizophrenia up to that time.

Before he moved to this area, Dr. Shakow was for many years chief psychologist and director of psychological research at Worcester State Hospital in Massachusetts. There he initiated one of this country's first internship programs in clinical psychology. He also pursued his studies of schizophrenia. He later taught at the universities of Illinois and Chicago.

He published numerous works on psychotherapy, child development and psychoanalysis.

In 1975, Dr. Shakow received the American Psychological Association's Distinguished Scientific Contribution Award for his work on schizophrenia and his influence on other researchers and clinical psychologists. He received several other awards.

Dr. Shakow, who was born in New York City, earned bachelor's, master's and doctoral degrees in psychology from Harvard University.

He was a fellow of a number of psychological and psychiatric associations and served on the editorial boards of many professional journals.

He lived in Kensington, where he devoted much of his leisure time to his garden.

Survivors include his wife, the former Sophie Harap, of Kensington; two daughters, Alice Piller of Highland Park, Ill., and Naomi Connelly of London; a son, Alexander, of Washington; two sisters, Rebecca Eckstein of Washington and Zara Shakow, and a brother, Jacob, both of New York City, and nine grandchildren.