To evaluate the bioeompatibility of MIM 316L stainless steel, the percentage of S-period cells were detected by flow cytometry after L929 incubated with extraction of MIM 316L stainless steel, using titanium implant materials of clinical application as the contrast. Both materials were implanted in animal and the histopathological evaluations were carried out. The statistical analyses show that there are no significant differences between two groups (P＞0.05), which demonstrates that MIM 316L stainless steel has a good biocompatibility.