Due to the complexity and randomness of the crowd motion, it is not easy to establish the crowd-structure coupled governing equation. Therefore, the idea of the solution procedure for the coupled system of the single pedestrian and structure is extended to carry out the research of crowd-structure coupled system. Then based on the social force model and the deceleration mechanism as well as the self-stopped mechanism, the one-way pedestrian flow is simulated. The modified Differential Quadrature-Integral Quadrature (DQ-IQ) mixed method is used to solve the dynamic response of the structure under the moving stiffness-mass-damping model, which can demonstrate this method enjoys higher accuracy than the mode superposition method and can take enough higher modes into consideration. Additionally, the fact that the DQ-IQ mixed method can be used to solve the dynamic response of the structure subjected to the crowd is verified. The final results under random crowd show that the varying tendencies of structural modal parameters respectively changed with the the number of pedestrian acting on the structure, In order to more comprehensively and more scientifically measure the vibration function of the structure, the 1 s-RMS acceleration is introduced to weaken the interference effect of random fluctuation.