Manius Aemilius Mamercinus was a three-time consular tribune, in 405, 403 and 401 and also consul in 410 BC, of the Roman Republic.
Manius Aemilius Mamercinus had no known descendants and later Aemilii Mamercini trace their ancestry to his brother Lucius.
The consuls fought a successful war against the Aequi and the Volsci which resulted in the capture of the fortress of Arx Carventana.
He shared the office with Lucius Valerius Potitus (brother of his former colleague Volusus), Appius Claudius Crassus Inregillensis, Marcus Quinctilius Varus.
Outside of war there was continued civil strife within Rome with a conflict involving three of the plebeian tribunes, Marcus Acutius, Gaius Lacerius and Gnaeus Trebonius, over the Lex Trebonia.