Background: Increased secretion of cortisol in adipose tissue has been implicated a mediator of central obesity in adult human and animal studies. However, evidence on altered cortisol metabolism in childhood obesity has been limited. We aimed to examine whether circulating cortisol metabolites and their ratios reflecting steroidogenic enzyme activities are associated with obesity in girls. Methods: A total of 227 girls (131 control, 45 overweight, 51 obese; aged 7 to 13 yr) were enrolled. Serum cortisol metabolites and cortisone concentrations were analyzed by gas chromatography-mass spectrometry. Enzyme activities involving cortisol metabolism including 11β–hydroxylase, 11β-hydroxysteroid dehydrogenase (HSD) type 1, 3α-HSD were assessed from the ratios of steroid metabolites. Results: Allo-tetrahydrocortisol (allo-THF) levels were significantly higher in obese girls compared with overweight and control girls, but the concentrations of other cortisol metabolites were not significantly different by obesity status. Obese girls showed significantly increased activity of 3α-HSD and marginally increased activity of 11β–HSD type 1, respectively, compared with overweight and control girls. Partial correlation analysis revealed positive associations of waist-to-height ratio and body fat percentage with allo-THF levels and activities of 3α-HSD and 11β-HSD type 1. Girls with central obesity determined by waist-to-height ratio ≥ 0.5 had 1.3 times higher allo-THF levels (6.30ng/mL vs. 4.94 ng/mL). Also, activities of 3α-HSD and 11β-HSD type 1 were significantly higher in girls with central obesity than controls. Conclusions: Central adiposity in girls was associated with increased activation of 11β-HSD type 1, and increased metabolic clearance of cortisol by 3α-HSD. Further studies are needed to reveal whether metabolic derangement of obesity are related with altered cortisol metabolism in adolescents.