A semiconductor device according to an aspect of the invention comprises an n-type FinFET which is provided on a semiconductor substrate and which includes a first fin, a first gate electrode crossing a channel region of the first fin via a gate insulating film in three dimensions, and contact regions provided at both end of the first fin, a p-type FinFET which is provided on the semiconductor substrate and which includes a second fin, a second gate electrode crossing a channel region of the second fin via a gate insulating film in three dimensions, and contact regions provided at both end of the second fin, wherein the n- and the p-type FinFET constitute an inverter circuit, and the fin width of the contact region of the p-type FinFET is greater than the fin width of the channel region of the n-type FinFET.