Dielectric electroactive polymers have wide application prospects in research field of biomimetic robots due to the advantages such as large strain, high efficiency, high energy density, etc. 1-DOF rotary joint was designed based on the actuation principle of bionic joint and the characteristic of cylinder actuator. The electromechanical coupling model of DEAP (Dielectric electroactive polymer) of actuator was constructed based on the large elastic deformation theory, then the nonlinear relationship between input voltage and output angle of joint could be obtained by solving the equations iteratively, but this process of computing was timeconsuming. To avoid the complicated calculation, CMAC (Cerebellar model articulation controller) neural network and PD controller were combined to realize the nonlinear mapping between the output angle of joint and input voltage. Tracking control experiments were performed in tracking step and sinusoidal reference signals, which showed the feasibility of CMAC neural network control method, while reasons for long response time and phase difference were discussed in details.