BACKGROUND/AIMS: Gastric varices (GV) are one of the most serious complications of portal hypertension, but there is limited information on the clinical course of GV in Korea. The aim of this study was to elucidate the natural history of GV bleeding in Korean patients. METHODS: Of 604 patients with GV diagnosed between May 1995 and May 2005 at the Samsung Medical Center, 237 patients without a history of variceal bleeding or previous intervention for varices were investigated. The cumulative incidence rates of GV bleeding, long-term survival rates, and risk factors for GV bleeding were evaluated. RESULTS: The cumulative incidence rates of GV bleeding were 4.8%, 19.9%, and 23.2% at 1, 3, and 5 years after diagnosis, respectively. The overall survival rates were 88.6%, 53.2%, and 37.2% at 1, 5, and 10 years. In the univariate analysis, fundal varices, large (F3) GV, red color sign, and poor liver function (Child-Pugh class B or C) were significant risk factors for GV bleeding. In the multivariate analysis, large GV (hazard ratio 2.49) and poor liver function (hazard ratio 3.95) were the independent risk factors. CONCLUSIONS: GV bleeding was more frequent in patients with fundal varices than in patients with type 1 gastroesophageal varices, and large GV and poor liver function were risk factors for GV bleeding. Close observation and prophylaxis for variceal bleeding might be warranted in high-risk patients.