Dr. Willard H. Wright, 87, a specialist in tropical diseases who had served as a scientist director with the U.S. Public Health Service and the National Institutes of Health, died Saturday at Sibley Memorial Hospital after a heart attack. He lived in Washington.

Dr. Wright was a native of Findlay, Ohio. He earned a master's degree at American University and his doctoral degrees in veterinary medicine and parasitology at George Washington University. He served with the Army Veterinary Corps in Europe during World War I and with an Army epidemiological study in the Pacific during World War II. His decorations include the Legion of Merit.

He moved to the Washington area in 1927 when he joined the Department of Agriculture's headquarters here as a parasitologist. In 1936, he transferred to the National Institutes of Health as a researcher. He was chief of the laboratory of tropical diseases and assistant director of the National Microbiological Institute when he left NIH in 1945.

Dr. Wright was commissioned as a scientist director (colonel) in the Public Health Service in 1945. He retired in 1958.

He was the author of many scientific papers and articles and published a book on tropical medicine research. He was a frequent delegate to international congresses on tropical medicine and malaria and served as assistant secretary general for the Fourth International Congress in 1949.

Dr. Wright was a past president of the Helminthological Society of Washington, the American Society of Parasitologists and the American Society of Tropical Medicine and Hygiene. He was a member of the Academy of Medicine of Washington and the Cosmos Club.

Survivors include his wife, Dorothy, of Washington; two children, Mary Louise Campbell of Wilmington, N.C., and Retired Army Lt. Col. Robert E. Wright of Jacksonville Beach, Fla.; six grandchildren, and four great-grandchildren.