Abstract: Objective To explore the effect of exenatide on hypoxia status of patients with type 2 diabetes mellitus complicated with obstructive sleep apnea hypopnea syndrome(OSAHS). Methods Forty-three patients with type 2 diabetes mellitus complicated with OSAHS were selected and randomly divided into group A(n=21)and group B(n=22). Group A was treated with premixed insulin, and group B was treated with exenatide. The changes of metabolic indexes and hypoxia indexes before and after treatment were compared between the two groups. Results In group B, two cases were removed due to severe gastrointestinal reactions. Compared with those before treatment, the levels of glycosylated hemoglobin(HbA1C), 2-hour postprandial blood glucose(2 h PG)and insulin resistance index(HOMA-IR)after treatment in both group were significantly lower, and fasting blood glucose(FPG)in group A was significantly lower(P<0.05). Compared with group A, HOMA-IR was significantly lower and FPG was significantly higher in group B(P<0.05). Compared with before treatment, systolic blood pressure(SBP), waist circumference(WC), body mass index(BMI), body mass, liver fat content(LFC)and low density lipoprotein cholesterol(LDL-C)- decreased significantly after treatment in group B, and there were significant differences between group B and group A(P<0.05). There were no significant differences in hypoxia indexes before treatment between the two groups(P>0.05). After treatment, oxygen reduction index(ODI)decreased significantly and the lowest oxygen saturation at night(LSpO₂)increased significantly in group B(P<0.05), and LSpO₂ in group B was significantly higher than that in group A(P<0.05). After correction of gender and age, the partial correlation analysis of clinical metabolic indexes and hypoxia indexes at first visit in group B showed that WC was positively correlated with △ODI(P<0.05), BMI, serum creatinine(SCR)was positively correlated with △LSpO₂(P<0.05), and estimated glomerular filtration rate(eGFR)was negatively correlated with △LSpO₂(P<0.05). Conclusion Exenatide alone can improve blood glucose, blood lipid, insulin resistance, ODI and LSpO₂ in patients with type 2 diabetes mellitus and OSAHS.