Abstract: Objective To investigate the therapeutic effect of continuous subcutaneous insulin aspart infusion (CSII) in patients with chronic obstructive pulmonary disease with acute exacerbation(AECOPD) and type 2 diabetes mellitus. Methods 101 patients with AECOPD and type 2 diabetes mellitus were selected and stopped using oral hypoglycemic agents. Beside the routine theray for AECOPD, they were randomly divided into two groups: the continuous subcutaneous insulin aspart injection (CSII) (n=52) and the multiple subcutaneous human insulin injection(MSII) (n=49).In the CSII group, the basal insulin aspart was continuously injected under the skin and the loading dose of insulin aspart before three meals .In the MSII group, human insulin Novolin R was used before three meals and Novolin N at 22:00.The levels of blood glucose, glycemic control time, daily insulin dosage, the incidence of hypoglycemic attacks, effective percentage of AECOPD therapy and duration of hospitalization were compared between two groups. Results The levels of FBG and 2h postprandial blood glucose were significantly lower after therapy than before therapy in both groups, but the decreased extents of them in the CSII group were bigger than in MSII group (P<0.05). Effective percentage of AECOPD improvement,reductions of glycemic control time,hospitalization time and daily insulin dosage in the CSII group were superior to those in MSII group(all P<0.01). Incidence rate of hypoglycemia in the CSII group were lower than in the MSII group (P<0.05). Conclusions CSII treatment of patients with AECOPD and type 2 diabetes mellitus is more efficient than MSII in controlling blood glucose, decreasing glycemic control time and hospitalization time, reducing the daily insulin dose and the incidence of hypoglycemia and increasing effective therapeutic percentage of AECOPD.