Background: Transarterial embolization (TAE) is an effective procedure for the treatment of acute gastrointestinal bleeding (GIB). Factors associated with clinical success have not been well delineated. Purpose: To evaluate the technical and clinical successes of TAE for acute GIB in order to identify factors influencing clinical success and in-hospital mortality. Material and Methods: This was a retrospective study of 70 consecutive patients with GIB who underwent angiography and embolization between January 2004 and December 2011. The technical success rate, clinical success rate, and in-hospital mortality were calculated by percentage. Clinical parameters, angiographic, and embolization data were assessed for factors influencing clinical success and in-hospital survival using univariate and multivariate analysis. Statistical significance was set at P value <0.05. Results: The technical success rate was 98.6%. The primary clinical success rate was 71.4% and the secondary clinical success rate after repeat embolization was 78.6%. Bowel infarction was the most serious complication of three (4.3%) patients. Failure to achieve 30-day hemostasis can be predicted in patients who have one or more of the following factors: hemoglobin concentration <8 g/dL (P ¼ 0.004), coagulopathy (P ¼ 0.005), upper GIB (P ¼ 0.02), contrast extravasation (P ¼ 0.012), and more than one embolized vessel (P ¼ 0.005). In-hospital survival is affected by the amount of transfused packed red blood cells before embolization (P ¼ 0.008) and post-embolization bowel infarction (P ¼ 0.005). Conclusion: TAE is a feasible and effective management of acute GIB with high technical and clinical success rates. The factors influencing clinical success include hemoglobin concentration, coagulopathy, upper GIB, contrast extravasation, and more than one embolized vessel. The number of units of transfused packed red blood cells and post-embolization bowel infarction are important factors associated with in-hospital mortality.