The invention belongs to the field of plastic chopping machines, and particularly discloses a plastic bottle chopping machine with a cooling function. The plastic bottle chopping machine with the cooling function comprises a machine body and a feeding port; a rotating shaft is arranged in the machine body and is provided with a plurality of spiral cutting knives; first magnets corresponding to the spiral cutting knives are arranged on one side in the machine body; blind holes are formed in the spiral cutting knives and are internally provided with pistons which are provided with second magnets; springs are arranged on the second magnets; one end of each spring is fixedly connected with the corresponding spiral cutting knife; a water inlet valve and a water outlet valve are arranged between the spiral cutting knives and the rotating shaft in which a cold water chamber and a hot water chamber are formed; a cooling device is arranged below the machine body and is provided with a water inlet pipe and a water outlet pipe; the water inlet pipe is connected with the cold water chamber; and the water outlet pipe is connected with the hot water chamber. The plastic bottle chopping machine can make plastic bottles fall easily, and the plastic bottles cannot become soft when the temperature is too high.