Acute left-sided colonic diverticulitis can be categorized into complicated and uncomplicated. The surgical treatment for complicated diverticulitis can be divided into the sigmoid resection with stoma formation (Hartmann’s procedure) or sigmoid resection with anastomosis, accompanied by a protective ileostomy. In instances where patients with complicated left-sided diverticulitis are hemodynamically unstable, damage control surgery is indicated. Laparoscopic lavage serves as a bridging procedure for complicated diverticulitis with purulent discharge or classified as Hinchy 3, aiming to stabilize the patient for subsequent definitive surgery. This review will examine the surgical treatment of complicated left-sided diverticulitis, focusing on sigmoid resection with stoma (Hartmann’s procedure) and colonic resection with anastomosis. Additionally, the role of laparoscopic lavage in the treatment of complicated diverticulitis with purulent discharge will be explored.