Abstract: Thermoplastics have been widely used in petroleum, chemical, construction,urban gathering and transportation systems due to their superior performance. This work focuses on the corrosive behaviors of linear low-density polyethylene (PE-LLD) and polypropylene (PP) against sulfuric acid, nitric acid, hydrochloric acid, sodium hydroxide and sodium chloride solution.The research results indicate that the impact strength of PP was found to show a loss rate of 23.9 % after corrosion ina 10 wt % NaOH solution for one week, whereas the loss rate for PE-LLD was 22.6% after corrosion in a 10 wt% HCl solution for two weeks. The effect of H2SO4 solution with a concentration of 10 wt% on the melting enthalpy of PE-LLD was very noticeable, and the enthalpy value decreased by 54.4% after immersion corrosion for 6 weeks.