To investigate the changes of serum angiopoietin-like protein 3 (Angptl3) and adiponectin levels in patients with metabolic syndrome (MS) in order to understand their association with the MS.Serum Angptl3 and adiponectin levels were measured by sandwich ELISA in a group of 111 patients with MS and 152 normal controls.Serum adiponectin was lower in the MS patients than in the control subjects [4.22(1.01-23.29) microg/mL vs. 5.41(0.97-22.27) microg/mL, P0.05). Serum adiponectin was correlated to Angptl3 and high density lipoprotein-cholesterol (HDL-C)(P<0.001) and negatively correlated to body mass index (BMI), waist circumference (WC), waist to hip ratio (WHR), triglyceride (TG), fasting plasma glucose (FBG), fasting insulin (FINS) and homeostatic model assessment method-insulin resistance (HOMA-IR) (P<0.001). Serum Angptl3 was positively correlated with adiponectin (P<0.001). Serum adiponectin was found to be independently positive determinant for Angptl3 concentrations (b'=0.256, P<0.001). Adiponectin was inversely correlated with TG and HOMA-IR (b'=-0.234, -0.145, P<0.001).Adiponectin is decreased in MS patients and may be correlated to Angptl3.