The protectiveness and characterization of passive films formed at various potentials in H2S-containing environments were studied using electrochemical measurements and surface analysis method. The corrosion resistance of 316L in H2S-containing environment decreases with the applied potential. The Auger electron spectroscopy (AES) and X-ray photoelectron spectroscopy (XPS) results indicate that Ni participates in the film formation, which results in the corresponding enrichment in the passive film. The oxidization degree analysis indicates that metallic elements are present in the passive film. Sulfide ions are significantly favored in the passive film at higher potentials, which is responsible for the breakdown of passive film. (C) 2017 Elsevier B.V. All rights reserved.