In this communication, structural-transport-properties of polyether block amide (PEBA)-MFI zeolite mixed matrix membranes (MMMs) have been investigated with molecular simulation (MS) and Monte Carlo (MC) technique. The density profile, RDF, FFV and XRD characterization have been calculated to investigate the aforementioned MMMs microstructure and also sorption and diffusion structural dependence of CO2-CH4 and CO2-N-2 pairs. Sorption, diffusion, permeability and selectivity of natural gases including CO2, CH4 and N-2 by PEBA polymeric membrane filled with nano-zeolite (MFI type) have been examined to study the influence of MFI nanomaterial and nanomaterial loading content on the performance of the MMMs. By increase of MFI loading from 10 to 20 wt.%, permeability for CO2, CH4 and N-2 increases from 106.5 to 123.6, 4.75-4.74 and 1.28 to1.31, respectively. Structural analysis shows very good behavior for simulated membranes. Moreover, experiments show that simulation results for XRD and diffusivity are in good agreement with experiment results. (C) 2017 Elsevier Ltd. All rights reserved.