Objective:To investigate the expression of melatonin receptors(MT1,MT2) in BMSCs from adolescent idiopathic scoliosis patients. Methods:Twenty-eight volunteers were divided into two groups:AIS group consisted of 18 patients and control group consisted of 10 subjects. The human bone marrow anticoagulated by heparin was obtained from anterior superior iliac spine,and the BMSCs were isolated by density gradient centrifuge from the mononuclear cells,and then were cultivated and serial subcultivated in vitro. P3 cultures were analyzed by the flow cytometry to determine the surface antigens,and expressive intensity of melatonin receptors(MT1,MT2)was detected by RT-PCR. Results:Mononuclear cells were cultivated and subcultivated to P3 culture in vitro,which were analyzed by the flow cytometry,and demonstrated that the expanded mononuclear cells expressed mesenchymal cell markers. There was no statistical difference of melatonin receptors expression in BMSCs between AIS group and control(P > 0.05). Conclusion:The expression of melatonin receptors in BMSCs were comparable between AIS patients and controls,which indicated that melatonin receptors would not involved in the pathogenesis of AIS in the stem cell level.