OBJECTIVE Although rectal varices constitute an important cause of lower digestive tract bleeding in patients with portal hypertension, the etiology and pathology of rectal varices remains controversial, and adequate treatment for rectal varices has yet to be established. In this study, we evaluated rectal varices to identify any common characteristics of varices which are susceptible to hemorrhage. METHODS The patients included 40 individuals with rectal varices among 425 patients with portal hypertension who had been treated in our institution. We retrospectively examined patient data regarding underlying hepatic diseases, hepatic function and endoscopic findings with regard to varices. RESULTS Bleeding from rectal varices occurred in 15 of the 40 patients. Although the prevalence of hemorrhage tended to increase with exacerbation of hepatic dysfunction, no significant differences were found. Similarly, although the incidence of hemorrhage tended to be somewhat higher in patients who had undergone any treatment for complicated esophageal varices than in patients who had not, no significant difference was found. The prevalence of hemorrhage from rectal varices significantly increased in rectal varices of more advanced form, and the prevalence was significantly higher in patients with positive "red color" sign. CONCLUSIONS The prevalence of hemorrhage from rectal varices was significantly higher in patients with rectal varices of advanced form and/or with a positive "red color" sign.