Concrete pump truck boom belongs to large flexible manipulator, and it always works in adverse environment. Due to the influence of exciting force and concrete load, pump truck boom produces vibration, which affects the casting quality and boom strength. Aiming at the fixedpoint pouring working condition, the forces on the boom were calculated. The concrete pump truck boom’s rigidflexible coupling model was established based on ANSYS and ADAMS software, and both of the high pressure and low pressure working condition were simulated, and its strength was calculated, which showed that the boom could meet the design requirements. The simulation results show that this method is suitable for the simulation of large flexible mechanical boom, and it could provide theoretical guidance for such structure’s design and checking.