Cooling apparatus of the underfloor system for a vehicle

A base plate which underfloor equipment is mounted on the back side, a heat radiation portion for radiating conducted heat through the base plate from the underfloor devices mounted on the front side of the base plate, inlet possible and inflow traveling along the traveling wind side gap region between the cover a side opening which can flow the air surrounding the heat radiating portion has on both side surfaces facing the direction of travel of the vehicle, the side surface and the heat radiating portion of the cover on the side of the running wind flows to have a guide plate for guiding a running wind flowing from the side opening by closing at least a part of the gap area between the surface and the heat radiating portion connecting the both side surfaces in the cover to the heat radiating portion.