Polyphenylene sulfide (PPS) fiber is a kind of high-performance fiber. This paper aimed at investigating the acid resistant performance of PPS fiber. The corrosive action of PPS fiber in nitric acid (HNO3), sulfuric acid (H2SO4), hydrochloric acid (HCl), the mixture of HNO3 and HCl, the mixture of HNO3 and H2SO4, the mixture of HNO3, H2SO4 and HCl were researched. In addition, the influence of various acid concentrations on the performances of the PPS fiber was also studied in the paper. The acid-treated sample was analyzed by the fiber tensile instrument, the Fourier infrared spectrometer, and the scanning electron microscope (SEM) to observe the change of mechanical performance, configuration and appearance.