Gaius Atilius Regulus (fl. 257–250 BC) was a Roman Republican consul who twice held the consulship in the middle of the 3rd century (257, 250) BC. He seems not to be closely related to M. Atilius M.f L.n. Regulus, for the grandfather of Regulus Serranus was named Marcus. Most likely the grandfathers were brothers and the successive consuls of 257 and 256 were second cousins.