A semiconductor device includes: a substrate, a surface portion thereof serving as a drain layer; a first main electrode connected to the drain layer; an epitaxial layer formed on the drain layer; a base layer formed on the epitaxial layer; a source layer formed in a base layer surface portion; an insulated trench sandwiched by base layers; a JFET layer formed on trench side walls; an LDD layer formed in a base layer surface portion and connected to the JFET layer around a top face of the trench; a control electrode formed on a gate insulating film formed on an LDD layer surface part, on surfaces of source layer end parts facing each other across the trench, and on a base layer region sandwiched by the LDD and source layers; and a second main electrode connected to the source and base layers sandwiching the control electrode.