Giant colonic diverticulum are rare, with 103 reported cases in 95 patients. The experience of any one surgeon is limited. We aimed to retrospectively review our experience and to review the literature on origin, pathology, and management of this rare and unusual problem.Cases were identified by review of pathologic database and by computerized audit from three hospitals.Five giant colonic diverticulum were identified in four patients, and the pathology and management were reviewed.A definition and classification system of giant colonic diverticulum is suggested. Giant colonic diverticulum should be the universal term to cover all colonic diverticulum larger than 4 cm, and we suggest that there are two types based on histology. Literature review reveals 103 reported cases in 95 patients. Type I (87 percent) is a pseudodiverticulum, perhaps related to conventional diverticular disease, whereas Type II (13 percent) is a true diverticulum, which is probably a type of communicating cystic congenital duplication. These lesions tend to occur in the sigmoid colon (93 percent) and present with complications similar to conventional diverticular disease. In the presence of conventional diverticular disease, consideration should be given to anterior resection, and in the absence, diverticulectomy should be considered.