For a small concrete pump truck,distribution hydraulic system is a crucial component.The whole machines pumping performance and efficiency are determined by the system parameter matching.According to the system mechanism movement theory and hydraulic working principle,the parameters internal relation in the system working cycles were studied.The calculation models of the pump discharge and accumulator volume under working conditions of singlepumpsingleaction and doublepumpdoubleaction were established,and the valve specifications were calculated and the flow cycle table under two working conditions was obtained.In order to solve the problems of the distribution system of a new type of small concrete pump truck,such as weak starting ability of the oscillating cylinder,long time of the oscillating reversing,large reversing impact and discontinuous pumping,a hydraulic simulation model was established to get the distribution return oil pressure curve and the cylinder travel time curve.The pressure distribution characteristics were tested by using relevant instruments and equipment.According to the mathematical model and flow cycle table,the matching ability of the distribution hydraulic system was quantitatively analyzed,and the each components specific parameters in the system were calculated and compared with the actual parameters of the small concrete pump truck.The results show that the improved small concrete pump truck has a good operation effect.The research results provide reference for the improvement and optimization of system matching.