John H. Clark (May 18, 1849 in Oughterard, County Galway – July 26, 1922 in Philadelphia, Pennsylvania) was an Irish-American boxer.

He was born in Oughterard, County Galway, but spent most of childhood in England before moving to the United States.

Clark was a clog and jig dancer before pursuing a career in prize-fighting.

He was the Lightweight Champion of America for two streaks before losing to Arthur Chambers in 1879 following a 136-round bout.

He owned a billiard hall and boxing school in Philadelphia.