An ionic polymer-metal composite (IPMC) consisting of a thin perfuorinated ionomer membrane, electrodes plated on both faces, undergoes large bending motion when a small electric field is applied across its thickness in a hydrated state. On the other hand, when small load is applied on IPMC, the electric field is induced in the polymer membrane depending on the magnitude of loading. The characteristics of IPMC are ease of miniaturization, low density and mechanical flexibility. Therefore, it is considered to have a wide range of applications from MEMS sensors to actuators. In this paper, we developed the fabrication process of IPMC actuator with palladium electrodes, which have lower stiffness than the conventional IPMC actuator with Au or Pt electrodes. The deformation of IPMC actuator is evaluated under various solvents, various temperatures, and various frequencies of input voltages. We developed the numerical model of IPMC actuator that can change the solution temperature and the ion species and compared the simulation results to the experimental results.