The invention discloses a pressure stabilizing structure of a pneumatic paper cutting machine. The paper cutting machine comprises a base, the upper end of the base is provided with a cutting device,the cutting device comprises a cutting bracket connected to the upper portion of the base, a cutting tool extending towards the base is arranged in the cutting bracket, and the cutting tool is drivento move along the cutting bracket by a pneumatic device to cut paper; and the paper cutting machine is characterized in that the pneumatic device comprises an air pump and an air storage tank, the output end of the air pump is connected with one end of the air storage tank, the other end of the air storage tank is connected with the cutting tool, and the other end of the air storage tank is provided with a pressure regulating valve, and the air storage tank is matched with the pressure regulating valve to output compressed air with the stable pressure. According to the pressure stabilizing structure of the pneumatic paper cutting machine, cutting can be conducted at constant pressure to ensure that the cutting position is not deviated, and the whole processing precision of the paper is also not affected. The pressure stabilizing structure of the pneumatic paper cutting machine is simple in structure and novel in conception, has the unexpected technical effect, and is suitable for industrial production.