Passive air suspension systems are commonly used at present. Because the air springs of the passive air suspensions have stiffness defects and matching between the standard series of air bag stiffness and the vehicle parameters is unreasonable and can not be adjusted in a personalized manner, the vehicles adopting the passive air suspensions sway more seriously during running so that the passengers and the drivers often feel dizzy and uncomfortable, thus seriously affecting the comfortableness of the passengers and the safe driving of the drivers. The phenomenon has become the main reason for the problem that the popularization and application of the passive air suspensions in the passenger cars are seriously affected. The invention provides a buffer air chamber and air bag composite air spring. The air spring has the following beneficial effects: the air spring has simple structure and low cost; and the static stiffness of the air spring can be effectively improved by a buffer air chamber and a buffer orifice plug before an air bag is compressed to the limited block of a vehicle body by sudden bigger dynamic load, thus reducing impact of the dynamic load on the vehicle body.