Various Zn modified carbon nitride (Zn‐C3N4) were facilely prepared by one‐step thermal polymerization method, and were successfully used for the chemical fixation of CO2 to epoxides producing cyclic carbonates in the presence of KI co‐catalyst. The combination of binary heterogeneous Zn‐C3N4 and KI exhibited efficient catalysis for the coupling of CO2 and epoxides. The effects of different reaction parameters, including reaction temperature, CO2 pressure, reaction time, and catalyst loading on activities were discussed. The yield of propylene carbonate (PC) could reach 99% under the optimized reaction conditions (130 oC, 2 MPa, 5 h) without additional solvent used, and the selectivity was above 99%. The catalysts showed good recycle performance and versatility for the cycloaddition of CO2 to various epoxides. The possible reaction mechanism over Zn‐C3N4/KI catalytic system was proposed. The developed Zn‐C3N4/KI catalysts exhibited attractive application as simple, effective and ecofriendly alternative catalysts for CO2 effective utilization.