Colonic lipomas are uncommon, benign, submucosal adipose tumors that are usually asymptomatic. Large lipomas can cause symptoms such as constipation, abdominal pain, rectal bleeding and intussusception. We report the case of a 60-year-old man with a history of lower abdominal pain and pseudoobstructive symptoms. Colonoscopy revealed a large polypoid sessile lesion in the sigma. We used a standardized technique of polypectomy, preceded by submucosal injection of dilute 5 ml polygelin with epinephrine 1:10,000 solution, to fully resect large colonic lipomas. The lipoma size was 3.5 cm. No bleeding or perforation developed. Histology showed the polyp to be a submucosul lipoma. On follow-up, there was no residual lesion. Colonic lipomas larger than 2 cm can be safely and efficaciously removed using electrosurgical snare polypectomy technique. The technique of submucosal injection before resection and using an electrocautery snare appears to be safe and reduces the risk of perforation reported in the literature.