The present invention relates to an apparatus for recycling wasted heat using waste hot water that includes: a tub that charges and discharges waste hot water; a heat exchange unit that transfers the heat of waste hot water to cold water supplied to a shower bat; and an upper cover that the open upper portion of the tub, and is friendly to the environment by reducing the amount of fuel consumed to supply hot water and it is possible to reduce the fuel cost by the reduced amount of fuel consumption.