The present invention provides a gas-liquid auxiliary supporter for dry granulator including a hydraulic cylinder housing, a lower air piston, a plunger, an upper cover and an upper air piston, wherein the hydraulic cylinder housing is arranged with a hydraulic oil inlet, the lower air piston is arranged with an oil channel for hydraulic oil to flow through, an opening at one end of the oil channel connects to the hydraulic oil inlet on the hydraulic cylinder housing, while an opening at the other end of the oil channel is arranged on the lower end face of the lower air piston, the plunger is arranged in the opening arranged at the lower end face of the lower air piston, the upper cover is fixedly connected to the upper end face of the hydraulic cylinder housing, the upper air piston is disposed in the upper cover with sliding fit, a containing chamber is defined by the lower end face of the upper air piston, the upper end face of the lower air piston and the hydraulic cylinder housing. By adopting such structure, the gas-liquid auxiliary supporter can provide support when the dry granulator runs, and the supporting force can be withdrawn when dry granulator stops, and the supporting force provided can be kept at a constant value to ensure the dry granulator works stably.