Based on carbon nanotubes and Nafion ionic polymers, a biomimetic nano-composite actuator has been developed by use of casting methods. The multi-waited carbon nanotubes (MWNT) with diameters of 3-5, 4-6 and 10-15nm and length of 10-20 mu m are used to enhance the basic performance of polymer actuators, with respect to electrical conductivity and mechanical stiffness. The carbon nanotubes are well dispersed in the Nafion matrix solution, using ultrasonic treatment and high speed homogenizer. The composite films are manufactured using a simple casting method. The electroless plating technique is used to make electrodes at the bottom and top surfaces of the composite film. SEM and TEM are used to characterize the surface and micro-structures of the composite actuators. In this study, novel biomimetic nano-composite actuators are developed and compared, with respect to bending actuation performance and electrical power consumption.