The invention discloses a cooling water waste heat recycling system, which comprises a cold water tank, a circulating pump A, a heat production device, a hot water tank, a circulating pump B, a variable frequency pump, a plate type heat exchanger A, a circulating pump C, a small water tank, a heat pump unit, a circulating pump D, a hot water tank, a water supply pump, a plate type heat exchanger B and a cooling tower. The cooling water waste heat recycling system transfers the energy of cooling water to the heat pump by using the plate type heat exchanger A, and then converts the low temperature heat transferred by the plate type heat exchanger into high temperature heat energy by using the heat pump, the water in the hot water tank is used as a carrier of the high temperature heat energy, and the temperature is up to 60 DEG C, so that the use occasions are increased. According to the cooling water waste heat recycling system, the heat supplied to the heat pump is indirectly adjusted by using the plate type heat exchanger A and the variable-frequency pump, so that the temperature of water entering the heat pump of a third internal circulation is stable and is less than 32 DEG C, and the service life of the heat pump as well as the reliability and stability of the waste heat recovery are ensured. The normal temperature water injected in the hot water tank firstly passes through the plate type heat exchanger B, so that the energy consumption in the waste heat recovery process is reduced.