Abstract： Objective　To study the factors associated with the recurrence of pituitary adenomas after surgery. Methods　Ninety cases including 45 recurrent cases and 45 non-recurrent cases with follow-up from 10 to 20 years were studied. All the patients clinical feature and index of tumor cell proliferating rate were investigate. Results　Clinical feature showed that there was significant difference between two groups in tumor size, rate of complete tumor removal, percentage of necrosis, cyst components and apoplexy of the tumor tissue. Immunohisto chemical staining of proliferating cell nuclear antigen (PCNA) and Ki-67 nuclear antigen was applied for cell kinetic research. A high proliferating index (PCNA Index and Ki-67 Index) of tumor cell was strongly associated with recurrence. Conclusions　The tumor cell proliferating index could serve as one of objective and precise tools for prognostic prediction of pituitary adenomas.