Satyu Yamaguti (?? ??, Yamaguchi Sachu, 21 April 1894 – 11 March 1976) was a Japanese parasitologist, entomologist, and helminthologist.
He was a specialist of mosquitoes and helminths such as digeneans, monogeneans, cestodes, acanthocephalans and nematodes.
He also worked on the parasitic crustaceans Copepoda and Branchiura.
Satyu Yamaguti wrote more than 60 scientific papers and, more importantly, several huge monographs which are still in use by scientists all over the world and were cited over 1,000 times each.