© 2020 European Society of Endocrinology.Context: Obesity and cardiometabolic diseases are associated with highe r long-term glucocorticoid levels, measured as scalp hair cortisol (HairF) and cortisone (HairE). Cardiometabo lic diseases have also been associated with copeptin, a stable surrogate marker for the arginine-vasopressin (AVP) syst em. Since AVP is, together with corticotropin-releasing hormone (CRH) an important regulator of the hypothalamic-pituit ary adrenal axis (HPA axis), we hypothesize that AVP contributes to chronic hypercortisolism in obesity. Objective: To investigate whether copeptin levels are associated with Hig her HairF and HairE levels in obesity. Design: A cross-sectional study in 51 adults with obesity (BMI ≥30 kg/m2). Methods: Associations and interactions between copeptin, HairF, HairE, and cardiometabolic parameters were cross-sectionally analyzed. Results: Copeptin was strongly associated with BMI and waist circumfere nce (WC) (rho = 0.364 and 0.530, P = 0.008 and <0.001, respectively), also after correction for confounders. Th ere were no associations between copeptin and HairF or HairE on a continuous or dichotomized scale, despite correction for confounders. Conclusion: In patients with obesity, AVP seems not a major contributor to the frequently observed high cortisol levels. Other factors which stimulate the HPA axis or affect cortisol sy nthesis or breakdown may be more important than the influence of AVP on long-term glucocorticoid levels in obesity.