Purpose : To evaulate the efficacy and safety of emergent superselective transcatheter embolization forcontrolling massive colonic bleeding. Materials and Methods : Six of the seven patients who had symptom of massivegastrointestinal bleeding underwent emergent transcatheter embolization for control of the bleeding.Gastrointestinal bleeding in these patients was originated from various colonic diseases ; rectal cancer(n=1),proctitis(n=1), benign ulcer(n=1), mucosal injury by ventriculoperitoneal shunt(n=1), and unknown(n=2). Allpatients except one with rectal cancer were critically ill. Superselective embolization were done by using Gelfoamparticles andor coils. Results : The vessels embolized were ileocolic artery(n=2), superior rectal artery(n=2),inferior rectal artery(n=1), and middle and inferior rectal arteries(n=1). Hemostasis was successful immediatelyin all patients. Two underwent surgery due to recurrent bleeding developed 3 days after the procedure(n=1) or inassocialion with underlying rectal cancer(n=1). On surgical specimen of two cases, there was no mucosal ischemicchange. Conclusion : Transcatheter embolization is a safe and effective treatment of method for the control ofmassive colonic bleeding.