The water-cooled cooler is composed of two parts: the Outer Shell and the inner shell. The outer shell comprises a cylinder, a water distribution cover and a backwater cover. The utility model is provided with an oil inlet and an oil outlet pipe, an oil outlet pipe, an air outlet pipe, an air outlet screw plug, a zinc rod mounting hole and a thermometer interface. The thermal medium of the water-cooled cooler is from the nozzle inlet on the cylinder body, and it flows meandering to the nozzle outlet through each zigzag passage in sequence. The Cooler medium adopts two-way flow, that is, the cooler medium enters one half of the cooler tube through the water inlet cover, then flows from the return water cover into the other half of the cooler tube into the other side of the water distribution cover and outlet pipe. In the process of double-pipe flow, the waste heat from the absorbing heat medium is discharged by the outlet, so that the working medium maintains the rated working temperature.