A new ionomer of sulfonated ethylene vinyl alcohol copolymer, EVOH-g-SO3H was synthesized and the ionic polymer metal composite (IPMC) based on EVOH-g-SO3H polymer has been produced through electroless deposition of platinum on the bare polymer membranes. The actuation performance for IPMC actuator was tested in order to set up a relationship between the structure and the behavior. The morphology of deposited platinum on the surface of the bare polymer membranes was studied by scanning electron microscopy (SEM). The actuation testing showed the IPMC have an apparent actuation under the electric strength of 30-180V/mm and the influence of the polymer chemical construction, the ion-exchange capacity (IEC) and the average effective electrode thickness (AEET) on the actuation performance of IPMC actuator were discussed in detail. Results showed the starting response voltage and the displacement of IPMC actuator increases with IEC or AEET increasing at certain extent and the EVOH-g-SO3H based IPMC could be used as a candidate material for soft actuators, sensors and artificial muscles