Purpose : The purpose of this study is to demonstrate the direct inhibitory effect of Hyulbuchukeotang on the proliferation of uterine leiomyoma cells through an experiment treating uterine leiomyoma cells cultivated by explantation with indicated concentrations of Hyulbuchukeotang and to research the gene expression related to cell cycle ill order to discover the connection with apoptosis and its mechanism by analyzing cell cycle. Methods : After primary culture of uterine leiomyoma cells, the cultivated uterine leiomyoma cells were treated with indicated concentrations of Hyulbuchukeotang for 24 hours. The inhibitory effect on the cell proliferation was determined by the cell count assay. The value of a cell count assay represent the percentage of cells in a phase of the cell cycle compared with total cells. In addition, a link between Hyulbuchukeotang and apoptosis was examined through flow cytometric analysis by FACS and DNA fragmentation analysis. Finally, the degree of gene expression related to cell cycle was evaluated by Western blot analysis. Results : The inhibitory effect of Hyulbuchukeotang increase of uterine leiomyoma cells treated with indicated concentrations of Hyulbuchkeotang increases. The result of gene expression related to G1 phase after treating with 100, 250, 500, 1,000 ${mu}g/ml$ concentrations of Hyulbuchukeotang. on uterine leiomyoma cells is that the gene expression of p27 was increased but that of p53 an p21 remained unchanged and the gene of pRB, pro-caspase 3 was decreased. Conclusion Through the mentioned experiments, it is demonstrated that Hyulbuchkeotang is effective in inhibiting Proliferation of uterine leiomyoma cells by extending cell cycle G1. However it is not considered that the inhibitory effect results from the aptoposis.