Hajime Hosokawa (細川 一, Hosokawa Hajime, 23 September 1901 – 13 October 1970) was director of the company hospital attached to the Chisso Corporation's chemical factory in Minamata, Kumamoto prefecture, Japan. He was the first doctor to discover and treat patients of the massive outbreak of mercury poisoning that occurred in the town, which became known as Minamata disease.