A power module includes: an encapsulation-target portion having at least one semiconductor element; and an encapsulation member that has first and second planes between which the encapsulation-target portion is interposed, and that encapsulates the encapsulation-target portion. The encapsulation member has, on the at least one semiconductor element, at least one opening that exposes part of a surface of the encapsulation-target portion the surface being on a side of the first plane. Thus, a semiconductor device of which size can be reduced can be provided.