This paper studies the gas transport properties of PES-nanosilica hybrid mixed matrix membrane for biogas purification. Problem statement: The hybrid mixed matrix membrane was produced to improve the membrane separation performance for biogas purification. The membrane was produced via dry-wet phase inversion method, in which the nanosilica was incorporated into polyethersulfone membranes and the prepared membrane was performed on biogas separation experimental test. Quantitative result: The SEM images analysis confirmed that nanosilica surface had taken important role in gas transport properties. Moreover, the nano-gaps (voids) between polymer and nanosilica particles were disappeared in the polyethersulfone hybrid mixed matrix membrane. The results revealed that the good nano-silica dispersion leads to enhance the properties of gas permeation up to 200% and slighly increased the selectivity about 0.9% of the nanosilica concentration 8 wt-%. Conclusion: It can be concluded that incorporation of nanosilicas particles into the matrix of polyethersulfone polymer significantly enhanced the membrane structure and separation properties.