Mixed matrix membranes (MMMs), combining the advantages of polymer membranes and porous materials, processing the potential to realize large-scale gas separation applications.However, the interfacial defects in MMMs greatly hindered gas separation performance improvement.Therefore, designing an MMM with high loading and good interfacial compatibility remains a critical issue in promoting the application of MMMs.Herein, during in-situ heating process, the melting of liquid ZIF-62 in PBI polymer can largely fill the interfacial defects in MMMs.The microporous transport channels of ZIF-62 glass in MMMs promoted the H2 diffusion and inhibited the CO2 and CH4 diffusion, thus enhancing the H2/CO2 and H2/CH4 separation of MMMs.For mixed gas testing, the 45 wt% ZIF-62 glass/PBI membrane had the maximum H2 permeability of 459 barrer, and its H2/CO2 and H2/CH4 selectivities were 23 and 57, higher than the gas separation upper bonds.In addition, ZIF-62 glass/PBI membrane exhibited stable separation performance under 1-5 bar pressure.Therefore, the rational combination of MOF glass and polymer matrix could provide promising potential for reducing the interfacial defects of high-loading MMMs, thus enhancing the gas separation performance.