The invention belongs to the technical field of performance test of a mining explosion-proof diesel engine, and particularly relates to a coolant temperature control circulating system for the performance test of the mining explosion-proof diesel engine, which solves the problem that the boiling phenomenon exists during the performance test of the existing mining explosion-proof diesel engine. A coolant outlet of the explosion-proof diesel engine comprises two branches; one branch is connected with an outlet of an expansion water tank; the other branch is connected with a coolant inlet of a plate heat exchanger; a coolant outlet of the plate heat exchanger is connected with a coolant inlet of the explosion-proof diesel engine; a cylinder cover of the explosion-proof diesel engine is provided with a cylinder cover water channel; the cylinder cover water channel is connected with an inlet of the expansion water tank; an exhaust manifold water channel of the explosion-proof diesel engine is connected with the inlet of the expansion water tank. According to the coolant temperature control circulating system for the performance test of the mining explosion-proof diesel engine, the problems of air resistance and boiling existing in the system under the condition of long-time operation at full load during the test process can be effectively solved, the temperature of the coolant can be controlled, the temperature of the coolant inlet and the coolant outlet and the coolant flow can be detected on line.