The invention discloses a pump truck stability control system, which comprises a detecting device and a controlling device, wherein the detecting device is used for detecting current pumping state parameters, boom posture parameters, landing leg posture parameters, pump truck body position state parameters and current numerical signals of external load parameters acting on a boom system of a pump truck, and the controlling device is used for receiving the current numerical signals of the above parameters, calculating the complete machine gravity center position of the concrete pump truck according to the parameters, and performing stability control for the pump truck according to the position of the complete machine gravity center in a pump truck stability area. The stability control system comprehensively takes pump truck own factors and external load influence factors into consideration, gravity center computational precision is high, and construction safety of the concrete pump truck is enhanced. In addition, the invention further provides a pump truck stability control method and a pump truck comprising the pump truck stability control system.