A power module includes: an insulating layer; a leadframe disposed on the insulating layer; a semiconductor chip disposed on the leadframe; and a mold resin formed so as to cover the semiconductor chip and at least a part of the metal layer, wherein a groove into which a part of the insulating layer is inserted is formed on a surface of the leadframe facing the insulating layer. Accordingly, there can be provided the power module with improved reliability so that the insulating layer and the leadframe may be hardly deviated from each other even if external force is applied thereon; and a fabrication method for such a power module.