Abstract: Provided is a water supply apparatus (100) including: a cooling tank (1), a refrigerating systems and a heat exchange device (4). The cooling tank is provided with a cold water outlet (11) and suitable to connected to water source; the refrigeration system comprises a compressor (31), a condenser (32), a throttling device (33) and the evaporator (34). The heat exchange device (4) is arranged outside the cooling tank (1) and provided with a water inlet (41) and a water outlet (42) communicating with the inside of the cooling tank (1), wherein the heat exchange device (4) is constructed such that water in the cooling tank (1) flows into the heat exchange device (4) from the water inlet (41) and performs a heat exchange with the evaporator (34), the water after the heat exchange flows out from the water outlet (42) and flows back to the cooling tank (1).