In this paper,the feasibility and clinical significance of left hemicolectomy colocolostomy in treating the obstruction of the left colonic cancer were discussed.Preoperative preparation,intraoperative and postoperative treatments in 12 patients with the obstruction of the left colonic cancer who received left hemicolectomy colocolostomy were studied retrospectively.Radical resection was performed in all 12 patients.There was only 1 case of incision infection.No fistula of the anastomotic stoma was seen.From the results,left hemicolectomy colocolostomy was feasible in those with permitted situation,enough blood supply of colon without obvious colonic swelling and inflammation.The fistula of the anastomotic stoma was avoidable when the ways of preoperative preparation,intraoperative and postoperative treatments were emphasized.For reducing the economic burden of the patients,duration of hospitalization,avoiding suffering operation twice,especially improving the prognosis,it may be the best choice to resect the left colonic cancer in I stage.