The utility model discloses a mine air flow cooling system based on a constant-temperature layer cold water source. The system comprises a constant-temperature layer cold water source, a water inlet pipeline, a water pump, a heat exchanger, an air inlet duct, a fan, an air outlet duct and a water return pipeline, the constant-temperature layer cold water source is sequentially connected with the water inlet pipeline and one end of the heat exchanger through the water pump, the air inlet duct is sequentially connected with the fan and one end of the heat exchanger, and the water return pipelineand the air outlet duct are connected with the heat exchanger; constant-temperature water flow of a constant-temperature layer cold water source meeting the underground ventilation and cooling requirements is directly used as a secondary refrigerant, heat exchange is conducted between the heat exchanger and ventilation air flow, the purpose of reducing the air temperature is achieved, a compressor refrigeration part is omitted, the equipment and power consumption cost is reduced, the whole air flow cooling system is simpler, and the arrangement mode is more flexible and diverse.