A wide gap semiconductor device has: a drift layer 12 using a first conductivity type wide gap semiconductor material; a well region 20, being a second conductivity type and provided in the drift layer 12; a polysilicon layer 150 provided on the well region 20; an interlayer insulating film 65 provided on the polysilicon layer 150; a gate pad 120 provided on the interlayer insulating film 65; and a source pad 110 electrically connected to the polysilicon layer 150.