A securing structure for a solar cell module installed on a roof of a building, having an external thread portion extending upward from a placement member, at least one flat plate-like shim member having a slit through which the external thread portion passes and a through-hole and stacked on the placement member, a flat plate-like connecting member placed on the shim member having an insertion hole through which the external thread portion passes, a droop portion drooping in the groove of the placement member through the through-hole, and a plurality of upward projecting portions projecting upward and sticking in the solar cell module and being made of an electrically conductive material, and a first securing member and a second securing member pressing downward on the solar cell module and the solar cell module placed on the connecting member with the external thread portion screwed into an internal thread portion.