A semiconductor device includes: a first-surface-channel-type MOSFET having a first threshold voltage; and a second-surface-channel-type MOSFET with a second threshold voltage having an absolute value greater than an absolute value of said first threshold voltage. The first-surface-channel-type MOSFET includes: a first gate insulating film formed on a semiconductor substrate; and a first gate electrode, which has been formed out of a poly-silicon film over the first gate insulating film. The second-surface-channel-type MOSFET includes: a second gate insulating film formed on the semiconductor substrate; and a second gate electrode, which has been formed out of a refractory metal film over the second gate insulating film. The refractory metal film is made of a refractory metal or a compound thereof.