Abstract： Objective To estimate the expression of ER and PR in the endometrium of both intrauterine adhesions (IUA) and non-IUA specimens. Methods The endometrium specimens from patients undergoing hysteroscopy for confirmed moderate IUA (n=20: 10 in proliferative phase, and 10 in secretory phase) were enrolled as the IUA group in Beijing Obstetrics and Gynecology Hospital from October 2014 to August 2015. The specimens scheduled for hysteroscopy due to infertility were recruited into the control group (n=26: 13 in proliferative phase, and 13 in secretory phase). Immunohistochemistry and&nbsp;quantificational real-time PCR (qRT-PCR) were used to detect the expression of ER-α, ER-β and PR in endometrium with different menstrual period in both groups. Results (1) Location: in both groups, the expression of ER-α, ER-β and PR appeared in the endometrial glandular epithelial cells and the stromal cells of the endometrium. The positive brown granules of ER-α, ER-β and PR appeared mainly in cell nucleus. (2) ER-α and ER-β in the endometrium:the protein expression of ER-α and ER-β in IUA group (proliferative phase: 0.657 ± 0.028, 0.493 ± 0.023; secretory phase: 0.537 ± 0.020, 0.365 ± 0.031) were significantly higher than those of control group (proliferative phase: 0.586 ± 0.025, 0.437 ± 0.022; secretory phase:0.459 ± 0.025, 0.323 ± 0.017;all P<0.01). And the ER-αand ER-βmRNA expressions in IUA group were 2.524 ± 0.296, 1.947 ± 0.339, higher than those of control group in the proliferative phase (all P<0.01), and in the secretory phase (1.977±0.333, 1.345±0.292) were also higher than those in the control group (all P<0.01). (3) PR in the endometrium: the protein expression of PR was not significantly different between IUA group (proliferative phase:0.248±0.025, secretory phase:0.194±0.024) and control group (proliferative phase: 0.234 ± 0.019, secretory phase: 0.186 ± 0.020; P=0.162, 0.359). Meanwhile, there were no statistical differences in the mRNA expression of PR in both groups with different menstrual period (proliferative phase: 1.144 ± 0.384 versus 0.981 ± 0.306, secretory phase: 0.763 ± 0.237 versus 0.631 ± 0.203; P=0.270, 0.166). (4) ER and PR expression in menstrual cycles: the expression of ER-α, ER-β and PR in the IUA group changed with the menstrual cycles, and their expression in the proliferative phase were higher than those in the secretory phase (all P<0.05). Conclusions The expression of ER-α and ER-β in the endometrium of IUA patients changes with menstrual cycle, and are higher compared with those in normal endometrium. No difference is found in the PR expression between the two groups.