The dielectric electroactive polymers(DEAP) have shown great promise in the field of biomimetric robotics due to their outstanding abilities such as large deformation,high efficiency and energy density. A bending DEAP actuator was designed and implemented. According to the theory of large elastic deformation,an electromechanical coupling model of the actuator was establised in this paper.By solving the differential equations, the relationship between the bending angle and lateral force have been obtained.The experimental results show that the actuator can bend with an angle of 75° and the maximum lateral force reaches to 0.7 N at 5 kV.The predictions of the actuator behavior agree well with the experimental results. Based on this actuator, a crawling robot was developed and preliminary experiment has proved the feasibility of the acutation in biomimetic robots.This work presents a novel actuation technology for the bionic robot.