This study aimed to investigate new biomarkers of obesity particularly in relation with inflammation-associated proteins using protein differential display techniques.Comparison of protein expression in plasma between non-obese (n=109, body mass index, BMI<25kg/m(2)) and obese (n=32, BMI≥25kg/m(2)) groups was carried out using two-dimensional gel electrophoresis (2-DE) analysis. ELISA was also performed for validation.Among six differentially expressed protein spots, ceruloplasmin (Cp) and fibrinogen were over-expressed in obese group. Plasma Cp levels were significantly higher in obese group than non-obese group (34.0 ± 8.6 vs. 41.3 ± 12.7mg/dL, p<0.001) and positively correlated with age (r=0.253, p<0.005), BMI (r=0.265, p<0.001) and hsCRP (r=0.385, p<0.001). In stepwise multiple linear regression analysis, plasma Cp along with hsCRP were found predictors for obesity (adjusted β-coefficient=0.266, p<0.01).Elevated plasma Cp levels were significantly associated with obesity, which may be suggested to be a marker of obesity.