James Curtis Hepburn (/ˈhɛpbərn/; March 13, 1815 – September 21, 1911) was an American physician, educator, translator and lay Christian missionary.

He decided to go to China as a medical missionary, but had to stay in Singapore for two years because the First Opium War was underway and Chinese ports were closed to foreigners.

Samuel Robbins Brown and all were quickly absorbed into the local foreign community, Hepburn being appointed honorary physician to the US Consul, Townsend Harris.

Hepburn's first clinic failed as the Bakumatsu authorities, wanting the missionaries to relocate to Yokohama, put pressure on patients to stop going to it.

In May 1867, with the collaboration of his long-time assistant Kishida Ginkō, Hepburn published a Japanese–English dictionary which rapidly became the standard reference work for prospective students of Japanese.