The invention relates to the technical field of equipment cabinet heat dissipation and discloses an equipment cabinet liquid cooling system, which comprises a plurality of equipment cabinets, whereinheat dissipation cabinets is arranged on the back sides of the equipment cabinets; a cooling coil is arranged in a cooling chamber; the cooling chamber is filled with a heat conductive medium; the lower end of the cooling coil on each equipment cabinet is connected to a main water inlet pipe through a branch water inlet pipe; the upper end of the cooling coil on each equipment cabinet is connectedto a main water outlet pipe through a branch water outlet pipe; and a water pump is disposed on the main water inlet pipe. The equipment cabinet liquid cooling system further comprises a double watersource heat pump which includes a condenser and an evaporator, wherein a return pipe is connected between the water outlet end of the main water outlet pipe and the water inlet end of the main waterinlet pipe, passes through the evaporator, and is provided with a valve A; a water tank is arranged between the return pipe and the main water inlet pipe; a valve B is arranged between the water tankand the main water inlet pipe; a valve C is arranged on the water inlet end of a hot water pipe; valves D are arranged on the branch water inlet pipes of respective equipment cabinets; and a valve E is arranged at the water inlet end of a cold water pipe. The equipment cabinet liquid cooling system has high heat dissipation efficiency and good dustproof performance.