A semiconductor device has a semiconductor substrate having an impurity-diffused region and a device isolation insulating film formed in the surficial portion thereof, a gate electrode formed on the semiconductor substrate, a contact formed on the gate electrode and connected to the gate electrode, and a protective film disposed between the semiconductor substrate and the gate electrode, below the connecting portion between the gate electrode and the contact, formed wider in width than the gate electrode in a sectional view taken along the direction of gate length of the gate electrode.