Abstract： Objective To investigate the significance of serum IP-10 levels in different types of diabetic patients. Methods Serum IP-10 level in 78 cases with type 1 diabetes,49 cases with type 2 diabetes and 33 cases of healthy controls was measured with ELISA assays. Type 1 diabetic patients were divided into classic type 1 diabetes (n=39) and latent autoimmune diabetes in adults (LADA,n=39) according to their disease process,and they were also divided into autoimmune type 1 diabetes (n=58) and idiopathic type 1 diabetes (n=20).Type 2 diabetic patients,according to carotid intima-media thickness (IMT),were divided into patients with (n=24) or without atherosclerosis (n=25). Results 1) Serum IP-10 levels were not statistically different among type 1 diabetes,type 2 diabetes and healthy controls. 2) Serum IP-10 concentrations in autoimmune type 1 diabetes with positive islet autoantibody were higher than those in healthy controls(184.96±104.48pg/ml vs 146.10±74.61pg/ml,P=0.03);while there were no difference in type 1 diabetes with variable disease durations. 3) No difference in IP-10 levels was found between type 2 patients with(173.5±69.6pg/ml) and without atherosclerosis (188.5±79.7 pg/ml). Conclusions Serum IP-10 level is augmented in autoimmune type 1 diabetes