Abstract： Objective To examine the expression of cell apoptosis repressor factor, Bcl-2 protein, celluar nucleus related antigen, Ki-67 antigen, estrogen receptor (ER) and progesterone receptor ( PR ) in eutopic and ectopic endometrium of adenomyosis and normal endometrium, and explore the pathogenisis of adenomyosis. Methods PicTure TM immunohistochemical staining technique was used to examine Bcl-2protein, Ki-67 antigen, ER and PR in 40 eutopic and ectopic endometrium of adenomyosis and 38 normal endometrium. The correlation among these factors was analyzed by Spearman. Results (1) The expression of Bcl-2 protein, Ki-67 antigen in eutopic endometrium of adenomyosis and normal endometrium showed obviously cyclic change. The expression level of them in proliferative stage was significantly higher than that in progestational stage (P＜0. 05 ). But in ectopic endometrium of adenomyosis, it showed no cyclic change. (2)The expression of Bcl-2 protein and Ki-67 antigen in ectopic endometrium of adenomyosis was significantly higher than that in eutopic endometrium of adenomyosis and normal endometrium (P＜0. 05 ), and it was higher in eutopic endometrium of adenomyosis than that in normal endometrium (P＜0. 05 ). (3)There was positive correlation of the expression of Bcl-2 protein and Ki-67 antigen with the expression of estrogen receptor and progesterone receptor in normal endometrium and eutopic endometrium of adenomyosis, but there was no correlation between them in ectopic endometrium of adenomyosis. Conclusion The abnormal expression of Bcl-2 protein and Ki-67 antigen in eutopic and ectopic endometrium of adenomyosis may be associated with pathogenisis of adenomyosis.