Abstract: AIM:To study the effects and its mechnism of methvlthioadenosine on apoptosis in RKO cells.METHODS:Hoechst 33258 staining was used to detect the effects of methyhhioadenosine on apoptosis in RKO cells,and the mRNA and protein level of cFLIP in this course was detected with the mothed of Realtime PCR and Western Blot.RESULTS:Methylthioadenosine could significantly induce apoptosis of RKO,and mRNA and protein level of cFLIP were downregulated significantly in this course.CONCLUSION:Methyhhioadenosine could induce apoptosis in RKO cells,and the downregulation of cFLIP gene misht olay a major role.