The invention provides a polyimide-modified material and a preparation method and application thereof. The polyimide-modified material is prepared by blending and granulating thermoplastic polyimide, aramid fibers, polytetrafluoroethylene and molybdenum disulfide through a twin-screw extruder, and forming the required specification by directly adopting injection molding in use. The polyimide-modified material is prepared from 50-90% of thermoplastic polyimide, 5-35% of aramid fibers, and 1-10% of other lubricants, such as polytetrafluoroethylene and molybdenum disulfide. The best novel guide ring material is compounded by combining good high temperature resistance, abrasive resistance and size stability of the thermoplastic polyimide, good flexibility and impact strength of the aramid fibers and low friction coefficients of polytetrafluoroethylene and molybdenum disulfide.