A hybrid control method was proposed to control the vibration of a spacecraft flexible structure by combining CMAC neural network (NN) and PID control method. Firstly, based on the given dynamic equation of the system, the neural network algorithm was obtained by using the concrete characteristics of CMAC neural network. Then, PID control method was introduced into the control system. The above processes form a hybrid control method, which combines the merits of CMAC neural network and PID control method. Finally, the numerical simulation of the complex flexible spacecraft showed that the proposed method was effective.