Objective:To investigate the effects of medicated serum of Liuwei Dihuang Pill on carboxylated and uncarboxylated osteocalcin in MC3T3-E1 cells, and further explore the common material basis of Liuwei Dihuang Pill in the treatment of osteoporosis and diabetes mellitus. MethodsThe suspension of Liuwei Dihuang Pill was prepared and given to the adult Wistar rats by intragastric administration, and then the medicated serum of Liuwei Dihuang Pill was collected. The cells were divided into the control group, medicated serum groups with low-, middle- and high-dose. The MC3T3-E1 cells were cultured for 22 days and starved for 24 hours, and then the culture medium was replaced by 10% medicated serum with different concentrations. After cultured for 24,8 and 72 hours respectively, 1 ml supernatant was aspirated from each group to detect carboxylated and uncarboxylated osteocalcin. The expression of osteocalcin mRNA was detected after cultured for 72 hours.  Results:Compared with the control group, the expression of osteocalcin mRNA was significantly increased in the medicated serum groups with low-, middle- and high-dose (P<0.01). For uncarboxylated osteocalcin in the supernatant,the contents in the medicated serum groups with middle- and high-dose were significantly higher than those in the control group and low-dose group at each timepoint (P<0.01, P<0.05).For carboxylated osteocalcin in the supernatant, the content in the medicated serum group with low-dose was significantly higher than that in the control group after incubated for 48 hours (P<0.01), and the contents in the middle- and high-dose groups were significantly higher than those in the control group at each timepoint (P<0.01). Meanwhile, the content in the middle-dose group was significantly higher than that in the low-dose group after incubated for 24 and 72 hours (P<0.05), and the content in the high-dose group was significantly higher than that in the low-dose group (P<0.01) and the middle-dose group (P<0.05) after incubated for 72 hours.  Conclusion:The medicated serum of Liuwei Dihuang Pill can promote the contents of carboxylated and uncarboxylated osteocalcin in the supernatant of MC3T3-E1 cells, which suggests that osteocalcin may be the basic material of Liuwei Dihuang Pill in treating two diseases, that is treating different diseases with the same method.