The invention relates to a high-reflectivity polypropylene film. The high-reflectivity polypropylene film is characterized in that the high-reflectivity polypropylene film is a film material consisting of polypropylene resin and inorganic filler in the mass ratio being (80-99): (1-20). According to the preparation method, a mixed material of the polypropylene resin and the inorganic filler is subjected to blended extrusion pelletization through a double-screw extruder, melted through a single-screw extruder and extruded by a die head at the temperature of 190-200 DEG C, a polypropylene base film with the thickness being 100-500 mu m is formed through flow casting on three rollers at the same speed with a flow casting method, cooled to the temperature of 25 DEG C and longitudinally stretched in a stretching ratio being 2-4 times at the temperature of 25-80 DEG C, and the polypropylene film is prepared. The polypropylene film has the density being 0.5-0.7 g/cm<3>, is 50-250 mu m thick, has the light reflectivity being 85%-97% at the wave bands from 440 nm to 740 nm and can serve as a high-reflectivity film to be used in illumination and other fields.