The surface charge accumulation on polymers often leads to surface flashover. Current solutions are mainly based on the introduction of inorganic fillers. The high-cost process and low compatibility remain formidable challenges. Moreover, existing researches on all-organic insulation focus on capturing electrons, contrary to alleviating charge accumulation. Here, an all-organic modification coating was prepared on polystyrene (PS) with the large-scale atmospheric-pressure plasma, which exhibits outperformed function in mitigating surface charge accumulation. The surface charge dissipation rate and surface conductivity are promoted by about 1.37 and 9.45 times, respectively. Simulation and experimental results show that this all-organic modification coating has a smaller electron affinity potential compared with PS. The decrease of electron affinity potential may result in accelerated surface charge decay of PS, which has never been involved in previous works. Moreover, this coating also has good reliability in a repeated surface flashover. This facile and large-scale approach brings up a novel idea for surface charge regulation and the manufacture of advanced dielectric polymers.