The issue of reducing CO 2 emissions is one of the most critical environmental problems. To this end, researchers have used various methods to eliminate this contamination from the industrial gas flow. Today, the use of investment costs, small size, light weight, no phase change during the membrane technologies in various industries has been widespread due to low metal, ceramic and polymer are used to prepare membranes. Polymer membranes are separation process, and less energy consumption. A wide range of materials like gas separation. The gas traort from polymer membranes is mainly controlled the most important option for membrane separation due to the good efficiency of by the Solution-diffusion mechanism. In this mechanism, the permeability is properties of polymer membranes. The chemical modification of the membrane, the obtained from the product of the solubility coefficient and diffusivity coefficient. In recent years, many efforts have been made to improve the polymer blending, the design of new block copolymers, and nanocomposite separations. membranes are the basis of the results of this research. The Polymer of Intrinsic Microporosity (PIM-1) based on Polyimide are a new group of polymers that have attracted researchers due to their excellent properties in gas In this research, the separation of carbon dioxide from methane and nitrogen was studied. Mixed matrix membranes (MMMs) based on the polymer of intrinsic microporosity and the covalent organic solvent to prepare it. Characterization tests like FTIR, XRD, TGA and FESEM on framework (COF) were prepared by phase inversion method and chloroform as a As the COF loading increased from 5 wt% to 7.5 wt%, nanoparticles tended to Mixed Matrix Membranes and Covalent Organic Framework nanoparticles was done. aggregate. In this research gas permeation properties for PIM-1/COF mixed 35° C and 2 bar pressure was investigated. The results showed that the carbon matrix membrane with 2.5-5-7.5%wt loading of COF at a constant temperature of dioxide gas permeation test increased from 1372.29 for pure PIM-1 membrane to 12879.13 for a PIM-1/COF membrane containing 7.5%wt COF. CO 2 /N 2 and CO 2 /CH 4 selectivity of mixed matrix membrane are significantly increased from 7.67 and 9.65 for pure PIM-1 membrane to 14.68 and 13.21 for PIM-1/COF-5. As the COF loading increased from 5 wt% to 7.5 wt, CO 2 /N 2 and CO 2 /CH 4 selectivity decreased from 14.68 and 13.21 to 13.82 and 11.14. The decrease in CO 2 /N 2 and CO 2 /CH 4 selectivity with increase CO 2 permeability was attributed to agglomeration of nanofiller and formation of COF clusters. Based on the results of the gas permeation test, the efficiency of the PIM-1/COF mixed matrix membrane improved gas separation, thus interrupting the Robeson upper-bound.