•PIM-1 showed excellent compatibility with MOF-801 filler.•The CO2-philic MOF-801 filler provided fast and selective transport channels for CO2.•MOF-801/PIM-1 mixed-matrix membranes revealed much higher CO2 permeability and CO2/N2 selectivity.•MOF-801/PIM-1 mixed-matrix membranes have good long-term working stability and good antiaging properties. This work mainly studies the CO2 separation performance of a new type mixed-matrix membranes (MMMs) based on MOF-801 as the microporous filler and PIM-1 as the polymer matrix. MMMs was successfully formed via simple casting/solvent evaporation approach at room temperature. The samples were systematically characterized by SEM, XRD, TGA and FTIR, the permeability-selectivity of MMMs to CO2, O2 and N2 was studied by gas permeability test. The experimental results show that the uniform dispersion of the CO2-philic MOF-801 filler provides a channel for the rapid and selective transport of CO2, so the MOF-801/PIM-1 MMMs revealed much higher CO2 permeability and CO2/N2 ideal selectivity (CO2 = 9686 Barrer, CO2/N2 = 27, all selectivity in the paper is ideal) than pure polymer membrane. After 90-days aging test, the CO2 permeability of MMMs remains above 70%, which reflects its good anti-aging performance. After 120 h continuous gas permeability test, it also shows good long-term working stability. The experimental results show that the good gas separation performance of MMMsexceeds the Robeson upper bound (2008), showing good application prospect for practical greenhouse gas CO2 separation.