Microelectromechanical system (MEMS), a technology of miniature devices comprises micropumps that are also crucial components in microfluidic analysis systems. This article provides comparative study that focused on numerical simulation of silicon, Polydimethylsiloxane (PDMS), Polymethyl methacrylate (PMMA) and Polyglycolic acid (PGA) actuator for piezoelectric micropump in order to determine which one is better. The aim and objectives of this study is to exhibit the usefulness of finite element analysis (FEA) and simulation techniques for selecting a better material for membrane attached on an actuator in a piezoelectric micropump. The piezoelectric micropump consists of actuator having piezoelectric disk coupled on membrane that can be made of different materials like silicon, PDMS, PMMA and PGA. The behavior of actuator like deflection and stress for different materials has been analyzed by applying voltage from 50 V to 150 V for varying frequency 50 Hz to 150 Hz. The maximum deflection at 150 V has been found for PGA that is 67 μm and minimum deflection comes out for silicon that is 16 μm while others PDMS has deflection of 25.2 μm and PMMA has deflection of 25.8 μm. This research work offers helpful information for piezoelectric micropump design.