Diverticulitis occurred in about 10-25% of diverticulosispatients; among them, 15%-20% would developcomplicated diverticulitis.5-7 As to complicationsrequiring surgery, it occurred in only approximately1% of diverticulitis cases.25 Our study focusedon those patients with complicated diverticulitis andneed surgical treatment. We compared the relationshipamong stage operation and several variants: mortality,morbidity, and lesion sites (left or right colon).The results showed no significant relationship amongstage operation with mortality, or lesion sites. Onlysignificant relationship between stage operation andmorbidity, and that between stage operation and hospitalstay were noted.