The invention provides an air cylinder with a buffering and protection function. The air cylinder comprises an air cylinder body, an air cylinder base and a buffering and protection device in fixed sealing connection with the upper end face of the air cylinder base, the air cylinder body is internally provided with a step-shaped cavity, after the lower end of the air cylinder body is in fixed sealing connection with the air cylinder base, the buffering and protection device is placed inside the step-shaped cavity, a second air nozzle communicated with the step-shaped cavity is installed at theouter side of the upper end of the air cylinder body, the step-shaped cavity is communicated with the buffering and protection device, and reverse high pressure air flow enters the buffering and protection device through a first air nozzle, so that after a piston in the buffering and protection device move upwards to switch off the buffering and protection device and an air channel of the step-shaped cavity, a number barometer is protected. After a first air chamber and a second air chamber in the air cylinder are switched off, the number barometer is protected while air pressure of the reverse high pressure air flow is reduced by the buffering and protection device, it is effectively avoided that the instantaneous reverse high pressure air flow clustered by the nozzle damages the numberbarometer, and the service life of the number barometer is prolonged while the number barometer is protected against damage.