The invention relates to a cooling device for an explosion-proof diesel engine. The cooling device mainly comprises a water cooling radiator, a water-air intercooler, a flame arrestor, left and right water cooling pressurizers, left and right water cooling exhaust manifolds, internal and external circulating water pumps, left and right exhaust seats, an air inlet pipe, an air outlet pipe, an air exhaust pipe, a water inlet pipe, a water outlet pipe, a water release pipe and a three-way valve, wherein the water cooling radiator and the water-air intercooler are adopted for realizing double cooling, the flame arrestor is used for resisting fire, the double water cooling pressurizers are used for pressurization and the internal and external circulating water pumps are used for water feeding;and a fan is arranged in the water cooling radiator for dissipating heat so that a high-power diesel engine can be well cooled during high-speed running, thereby guaranteeing the safety of running. The device has the advantages of reasonable and advanced design, compact, safe, stable and reliable structure, good use effect and fewer faults, is the ideal cooling device for the high-power diesel engine and can also be used on similar engines.