Persistent organic pollutants (POPs) are endocrine-disrupting chemicals associated with metabolic syndrome and type 2 diabetes. In humans, little is known about their potential role on obesity. Adiponectin augments the effects of insulin on glucose homeostasis. The expression of adiponectin is reduced in obesity, insulin resistance, and type 2 diabetes. The aim of this study is to reveal whether accumulation of the POPs, especially polychlorinated biphenyls (PCBs), is associated with serum levels of adiponectin in Koreans. This cross-sectional study includes 98 Koreans (49 men and 49 women). Serum levels of marker PCBs (PCB 28, 52, 101, 138, 153, and 180) were measured by Agilent 7890GC-micro-ECD (Gas chromatography-micro-electron capture detector). Total adiponectin levels were quantified by enzyme-linked immunosorbent assay. We defined high (≥Median) and low (<Median) body mass index (BMI) groups by using median value of BMI (24.6 kg/m2 for men; 23.0 kg/m2 for women). PCB28, PCB138, and PCB153 were significantly negatively associated with adiponectin levels (β-coefficients=-0.00741 for PCB28; -0.00438 for PCB138; -0.00406 for PCB153). When we divided subjects by sex, PCB28 and PCB153 were inversely associated with adiponectin in women. In the high BMI group (≥Median), PCB153 showed the significant negative associations with adiponectin levels (P<0.05). However, these associations were not seen in the low BMI group. In conclusion, we found negative associations between PCBs and adiponectin. This cross-sectional study could provide support for the hypothesis that POPs exposure might contribute to type 2 diabetes as well as obesity.