Herman Ossian Armour (March 7, 1837 – September 8, 1901) was an American businessman and philanthropist who with his brother, Philip Danforth Armour, co-founded the meatpacking firm of Armour & Company, which would exist as the nation's largest such company for much of the twentieth century. Armour was a delegate to the 1892 Republican National Convention and a presidential elector in the 1896 presidential election.