An on-board solar battery module includes: an encapsulant layer of power generating elements; a top surface layer joined to the encapsulant layer on the side corresponding to a light receiving surface side of the power generating elements; and a back surface layer joined to the encapsulant layer on the side opposite the side corresponding to the light receiving surface side of the power generating elements. Furthermore, an end portion of the back surface layer is positioned on the inner side of an end portion of the top surface layer in an extension direction of the top surface layer, and the top surface layer has a general portion that covers the power generating elements, and a peripheral edge portion that is formed at an end portion side thereof on the outer side of the general portion, and that has a thicker panel thickness than that of the general portion.