A liquid cooling system which is utilizable in a personal computer includes a pump for supplying a cooling liquid; a heat receiving jacket supplied with the cooling liquid and positioned to receive heat generated from a heat generation body, a heat radiation pipe for radiating heat which is supplied by the cooling liquid passing through the heat receiving jacket, and a passage for circulating the cooling liquid passing through the heat radiation pipe into the pump. The heat radiation pipe is made of material having a corrosion resistance that is higher than that of the heat receiving jacket.