Background: In postmenopausal women, decreasing estrogen levels is a marker of ovarian dysfunction. Hypoestrogenic state has known increasing the risk of osteoporosis. Objective: To determine the correlation between estradiol serum levels with classification of osteoporosis risk OSTA (Osteoporosis Self-Assessment Tools for Asian) in menopausal women. Methods: This study was case series study which examined estradiol serum in menopausal women by ELISA and assess the osteoporosis risk using osteoporosis risk classification OSTA. Total 47 samples were collected at Dr. H. Adam malik, Dr. Pirngadi, and RSU Networking in Medan. This research was conducted from May to December 2016. Data were statistically analyzed, and presented with Spearman test. Results: In this study we found the mean levels of estradiol in menopausal women was 18.62 +/- 16.85 ng / ml with OSTA osteoporosis risk score of 2.09 +/- 2.45. There were a significant positive correlation between estradiol and risk of osteoporosis OSTA with correlation coefficient r =0.825 and p <0.05. Conclusion: There is a strong positive correlation between serum levels of estradiol with OSTA osteoporosis risk assessment in menopausal women.