John H. Clark

John H. Clark may refer to:


 * John Harrison Clark (c. 1860–1927), Cape Colony adventurer who ruled much of southern Zambia
 * John Heaviside Clark (died 1863), Scottish aquatint engraver and painter of seascapes and landscapes
 * John Howard Clark (died 1878), editor of The South Australian Register, 1870–1877
 * John Clark (boxer) (1849–1922), Irish-American boxer
 * John H. Clark House, a historic residence in Mechanicsburg, Ohio named for a local John H. Clark