Truck-mounted concrete pumps have been adopted in many construction projects. However, the investigations about the automatization or robotization of distribution boom system of the truck-mounted concrete pump are very scattered. In this study, a scheme of automatic concrete spray of the distribution boom system of the truck-mounted concrete pump has been presented and discussed. The concrete spray process and the kinematics of the boom sections were analyzed including its inverse kinematics problem. Transient dynamic analysis was performed to validate the effect of the new control system on the boom system base on the flexible body co-simulation among ANSYS software, ADAMS software and Matlab/Simulink software. A three-dimensional simulation was programmed to imitate the process of automatic spray and verify the control algorithm. The simulation result shows that the system can pour concrete on a long narrow area automatically thereby satisfying, and the trajectory movement of boom mechanism.