We report a series of patients with severe radiation injury treated with endoscopic laser photocoagulation. Eight patients with recurrent lower gastrointestinal bleeding secondary to procosigmoiditis were treated with endoscopic Nd:YAG laser therapy. Patients were followed for an average of 21.7 months after the first laser treatment. Average transfusion requirements and hospital admissions per patient-month were 0.93 and 0.27, respectively, in the prelaser period and 0.18 and 0.06, respectively, in the entire period following the first laser treatment. A total of 26 laser treatments were performed. There were three major (prolonged ileus) and one minor (pain) complication. We conclude that endoscopic Nd:YAG laser photocoagulation is a safe, effective, and lasting treatment in severe, symptomatic radiation injury of the lower gastrointestinal tract.