PURPOSE: Diverticular disease of the colon is relatively common in western population and rare in oriental population but in recent years the incidence is steadily increasing in oriental population including Korean, so more concerns and appropriate management are required. METHODS: We reviewed 111cases who had diverticular disease in the colon from January 1988 to May 1998 in the Soonchunhyang University Chunan Hospital. Of 111 cases, 87 cases were treated conservatively and 24 cases received a surgical treatment. RESULTS: The annual incidence increased progressively for the last 10 years. The mean age of the patients at the time of diagnosis was 49.6 years and the most common age-group was forth decades (25%). The diverticula were located in the right colon 89%, left colon 7% and both side 4%. Among 24 surgically treated cases, the most common preoperative diagnosis was acute appendicitis (75%) and the correct preoperative diagnosis was made only 3 cases (13%) who had previous appendectomy history, previous diagnosed history or received barium enema due to recurrent pain attack. The surgical procedures of the colonic diverticulosis were right hemicolectomy (6 cases), ileo-ascending colectomy (6 cases), diverticulectomy (2 cases), segmental resection of transverse colon (1 case), left hemicolectomy (1 case), appendectomy (2 cases), appendectomy with drainage (3 cases), appendectomy with drainage and diverticulectomy (3 cases). The postoperative complication was wound infection in all complicated cases. There was no postoperative mortality. CONCLUSIONS: The outcome of patients in our series is satisfactory despite of diagnostic inaccuracies. Preoperative barium study is recommended in those above the 40 years of age suspected the appendicitis. We recommend surgery for patients after two or three episodes of acute diverticulitis that resolves after medical treatment with antibiotics.