The phytic acid self-assembled film ( SAM) was prepared on 316 L stainless steel surface before and after chemical oxidation by immersion method. The effect of SAM solution pH and SAM time on the adsorption behavior and corrosion inhibition performance of the phytic acid SAM was investigated by potential dynamic scan, SEM ( scanning electron microscope) observation and FT-IR ( Fourier transformed infrared spectroscopy) testing. The experimental results show that phytic acid has been successfully assembled to the surface of 316 L stainless steel,which greatly improves the corrosion resistance of the metal .The chemical oxidation pretreatment is beneficial for the formation of a denser SAM with more notable corrosion resistant performance. For the samples without chemical oxidation treatment, the optimum pH for the assembly of phytic acid is 6 . 90 and the best assembly time is 12 h. And for those with chemical oxidation, the optimum pH is still 6 . 90 while the best assembly time reduces to 4 h.