This study performs a simulation for an accumulation mechanism of contaminants, which were produced in an industrial belt of inland, on the surface of insulators. From the simulation, silicon insulators presented higher accumulation than that of EPDM(Ethylene Propylene Diene Terpolymer : EPDM) insulators on the same distance in the case of the Virgin polymer insulator, and this result presented the same result in the insulator applied in actual fields. In the case of the accumulation test for the Virgin insulator and insulators used in actual fields, it is evident that the Virgin insulator presented more accumulation than that of the insulator used in actual fields. The results can be caused by the generation of LMW (Low Molecular Weight) on the external material of polymer insulators, and the level of the accumulation can be changed according to the degree of the continuous generation of LMW. In order to simulate a certain pollution of an industrial belt, which is located along the coastline, leakage currents were measured by applying the contaminant compulsively that was produced with salts and Kaolin according to the ratio of its weight on the surface of insulators. The more increase in the content of Kaolin pollution, the level of leakage currents on the surface of polymer insulator more increased. In addition, the approaching time to the maximum value of leakage currents presented a nearly constant level regardless of the content of Kaolin. The level of leakage currents significantly decreased according to the passage of time, and the level of leakage currents on the surface maintained a constant level at a specific time regardless of the content of Kaolin.