Abstract: Dielectric elastomers can be used to make actuators which yield large strain,drive heavy load and have good plasticity.The working principle of such actuators and a basic method to make actuators with dielectric elastomers was introduced.The effects of electrodes and pre-strain on the performance of actuators were studied.Experimental results indicate that the plasticity of electrodes must be matching with the properties of the material.Stiffer electrodes reduce the strain,but softer electrodes make films easier to be destroyed.Large prestrian may reduce actuators' sensitivity but improve the magnitude of max strain of actuator.