Hermes Rodrigues da Fonseca (; May 12, 1855 – September 9, 1923) was a Brazilian soldier and politician. The nephew of Deodoro da Fonseca, the first Brazilian President, he was the country's Minister of War in 1906. In 1910, he was elected as the 8th president of Brazil, serving until 1914. He was on an official visit to Portugal when the revolution that overthrew the Portuguese monarchy and replaced it with a new republican regime took place.