The surface charge decay dynamics of polypropylene films charged with a negative corona were investigated experimentally, revealing a strong dependence on charging voltage levels and temperature. The findings indicate that both parameters significantly impact the surface potential decay behavior. At low temperatures, the decay rate differ markedly from that at high temperatures, with the decay rate increasing as the temperature rises. The increase in the surface potential decay rate suggests that polar groups introduced by plasma onto the polypropylene surface accelerate the dissipation of surface charges. These results are confirmed by the analysis of the chemical composition, as revealed by FTIR-ATR spectroscopy at high temperatures.