In an electronic equipment or apparatus, having water-cooling structure able to circulate/supply a cooling liquid with stability, for dealing with an increase of heat-generation of a heat-generating element, accompanying with an increase of processing performances, a pipe, which is located at a side where the cooling water flows out from a tank building up the water-cooling system, is extended up to the position of a center of the tank and disposed therein. Also, two (2) pieces of plates are provided for dividing the vicinity of an inlet portion of a pipe, through which the cooling water flows out, within the tank, and further, when injecting the cooling water into the tank, an injection jig for the cooling water is used, which has a connector portion with the tank.