Introduction: Giant colonic diverticulum (GCD) is a rare complication of colonic diverticulosis. Patients have often non-specific symptoms, and complication is exceptional. Case Report: We report a case of an 87-year-old man with several admissions in the last year due to episodes of acute diverticulitis and CT scan image compatible with GCD that presents with pain and a palpable abdominal mass. In urgent CT scan GCD shows increased size reaching 12 cm. Laparoscopic sigmoidectomy with primary colorectal anastomosis was performed urgently. His postoperative course was plain and the patient was discharged after 5 days. Pathology reported a diverticular formation of 12 cm in diameter. Discussion: Location and simultaneous acute diverticular disease are the main criteria for deciding the surgical approach. Colonic resection with primary anastomosis is the gold standard and, if possible, should be performed by laparoscopy, even in emergency cases.