The modified ZSM-5 commercial as a filler for the polyethersulfone membrane was investigated in this work. The modification of ZSM-5 was prepared from aqueous solution 0.25 M NaOH as long as 30 minutes and returned to H-ZSM-5 from by exchange with NH4-acetate and calcined at 550 °C. The ZSM-5 commercial and H-ZSM-5 were characterized by X-Ray Diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FTIR). XRD analysis showed the presence of ZSM-5 and the desilication treatment did not have a significant effect on the structural crystal phase of ZSM-5. The FTIR analysis shows support for XRD data that the similarity of the peaks and absence of any new bonding formation after the desilication process, it has vibrations of the pentacle and Si-O, Al-O skeletons peaks in 545 and 450 cm-1 which were characteristic of the ZSM-5. Modified ZSM-5 was as a filler in preparing the PES membrane by a phase inversion method. XRD data analysis shows that the composite membranes have characteristic peaks of ZSM-5 particle and amorphous PES and in the SEM image of cross section was seen as an asymmetrical membrane with tending a pore structure to be finger-like. The presence of ZSM-5 and PES in the composite membrane shows that ZSM-5 can be use as a filler in PES membranes.