Herein, a fiber-supported imidazolium-based ionic liquids catalyst in impellers of the agitation system was developed for efficient cycloaddition of CO2 with epoxides under metal- and solvent-free conditions. The fiber-supported ionic liquids catalyst was designed collectively and synthesized systematically, and characterized detailedly on the physicochemical properties via various technologies during both of the preparation and utilization processes. Moreover, the influence of ionic liquids structures and reaction conditions on the cycloaddition was inspected, and the fiber catalyst-mediated CO2 conversion proceeded smoothly (100 °C and 1 MPa) in gram-scale for the synthesis of organic carbonates in good to quantitative yields. Notably, the novel fiber catalyst in impellers of the agitation system also displayed prominent recyclability (21 cycles), and the protocol could be operated concisely with good prospect for industrial applications.