Argon plasma coagulation (APC) has been used extensively for a wide range of indications in gastrointestinal endoscopy. We describe a case of haemorrhagic radiation proctitis treated successfully with APC. A 54-year-old Japanese woman presented with daily rectal bleeding 4 months after cessation of radiotherapy for uterine cancer. Colonoscopic examination showed friable bleeding teleangiectasias in the rectum. Her haemoglobin level was decreased to 5.4 g/dl, requiring frequent blood transfusions. Endoscopic APC set at 1.2 l/min and 45 W was applied. After four treatment sessions without any complications, the patient showed complete resolution of haematochezia and subsequent haematological improvement. Standard and magnifying endoscopic follow-up revealed complete eradication of the vascular lesions and cicatrization of the treated areas, and mucosal covering with normal crypt lining. Endoscopic APC is an effective and well-tolerated treatment modality for the management of haemorrhagic proctitis.