Italian Americans in the Civil War are the Italian people and people of Italian descent, living in the United States, who served and fought in the American Civil War, mostly on the side of the Union. A contingent of soldiers from the former Kingdom of the Two Sicilies fought on the Confederate side, with most of these having been former prisoners of war who had fought against Giuseppe Garibaldi during his invasion of the Two Sicilies. Between 5,000 and 10,000 Italian Americans fought in the civil war.

Luigi Palma di Cesnola, an Italian-American soldier, diplomat and amateur archaeologist, was born in Rivarolo Canavese, near Turin. He received the Medal of Honor for his actions during the American Civil War. He was United States consul at Larnaca in Cyprus (1865–1877) and first Director of the Metropolitan Museum of Art in New York (1879–1904).