Uterine leiomyoma is the most common tumor in the female genital tract. Although the tumor is benign, it is of paramount importance since it often causes profuse menstrual bleeding, pressure symptoms, and infertility. Nevertheless, the etiology and patholphysiology of this abnormality remain poorly understood. The traditional definitive treatment for uterine leiomyomas is hysterectomy and, even today, symptomatic leiomyomas are the leading cause of hysterectomy in Korea. Clearly, the development of a safe, effective, and nonsurgical method of treatment for leiomyoma would be of great benefit to many women. The present study was designed to investigate the effect of Rhubarb on apoptosis in uterine leiomyoma cells. Results demonstrate that Rhubarb inhibited cell growth in dose-dependent manner. Cell growth significantly decreased to 60% of control in the treatment of Rhubarb (300㎍/㎖). Associated with the decreased response, there was a concomitant and significant delay of subG1 8.32% above baseline in the treatment of Rhubarb (300㎍/㎖). The delay of subG1 showed a dose-dependent manner, as evidenced by the flow cytometry. The reduced cellular viability on exposure to Rhubarb may represent the induction of apoptosis, at least in part, as concomitantly evidenced by enhanced DNA fragmentation, PARP cleavage and caspase 9 and decreased pro-caspase 3. In addition, Rhubarb decreased clAP1 expression levels in dose-dependent manner. Talcen together, there results suggest that Rhubarb can produce a potent inhibition effect of apoptosis and implicate the delay of G1 phase in the cell cycle and pathways of caspase 3 and 9 in the mechanism underlying inhibitory apoptosis effect of Rhubarb.