Henry Dukso Moon was born on September 28, 1914, in San Francisco, California. His father, Yang Mock Moon, a scholar and activist for Korean independence, had emigrated to the United States from Korea in 1903; his mother, Chan Sung Lee, had come to the United States from Korea as a "picture bride" in 1913. Henry Moon graduated from Galileo High School in San Francisco in 1931, and went to the University of California, Berkeley, where he received his A.B. degree in Medical Sciences in 1935, upon his completion of the first year of the curriculum of the University of California School of Medicine. From 1935-1937 he was a graduate student in Anatomy (M.S., 1937). While at Berkeley's Department of Anatomy and the Institute of Experimental Biology, he came under the influence of Professors William R. Lyons and Herbert M. Evans, and in Professor Lyons' laboratory he did much important work in studying ACTH that had been isolated and purified there from prolactin derived from sheep pituitary glands. His brother, Dr. William H. Moon, has noted that "Henry [Moon] was the first second-generation Korean to be born in San Francisco, and the first San Francisco-born Korean to graduate from U. C. Berkeley and U.C. Medical School in San Francisco."

Following his 1940 graduation from medical school, Dr. Moon served his internship and residency at San Francisco General Hospital, and completed his specialty training in pathology in 1944. His first faculty appointment at UCSF, as an instructor in pathology, came in 1943. From 1944 until 1947 he was on active duty in the U. S. Army Medical Corps at Letterman General Hospital, leaving the service with the rank of major. In 1947 he became chief pathologist for the San Francisco Coroner's Office and Chief of the Pathology Service at the Veterans' Administration Hospital. In 1956 he became a full-time faculty member at the University of California's Medical Center at San Francisco as associate professor of pathology (he was promoted to the full professorship in 1958) and as chairman of the Department of Pathology, a position he held until his retirement in 1974. He also served as professor and chairman of the Division of Forensic Pathology and Medicine.

Dr. Moon's research, begun at Berkeley in the 1930s, continued throughout his life. He authored or co-authored approximately 100 original scientific papers. His research covered many fields but he maintained an interest in anterior hypophyseal hormones; in the early 1950s, he co-authored with H. M. Evans, C. H. Li and M. E. Simpson a series of approximately ten papers dealing with neoplasms developing in rats chronically treated with hypophyseal growth hormone. He published extensive studies of arteriosclerosis both in man and in experimental animals, and also discussed the lysis of homologous cells by sensitized lymphocytes in a series of some ten papers that have been described as "ahead of their time."

Dr. Moon was past president of the American Society of Experimental Pathology, the International Academy of Pathology, the American Association of Pathologists and Bacteriologists, the California Society of Pathologists and the UC Faculty Alumni. He served on four different committees of the National Institutes of Health and on the Scientific Advisory Board, Armed Forces Institute of Pathology. He was twice a visiting professor as specialist for the U. S. State Department --first serving in Korea (1957) and then in the U.S.S.R. (1958).

Dr. Moon died in San Mateo, California, on August 2, 1974.