The alarming growth of obesity and related pathologies turned it an epidemic accordingly with the World Health Organization. Skin changes induced by obesity have already been documented but it is not established whether these disorders are a direct result of obesity or the expression of associated co-morbidities. Since it is important to understand obese skin alterations, particularly in terms of the “envelope” function, this study aims to contribute to better understand implications of weight gain on human skin’s physiology. A convenience sample of of 74 volunteers, female, healthy, aged 19 to 46 (32 ± 7) years old, was selected after informed consent, in accordance with previously established inclusion criteria and in full compliance with all ethical standards laid down by the Declaration of Helsinki and respective amendments. This sample was divided into three groups – Group I, BMI between 19.9 and 24.9 kg/m2(normal weight), Group II, with BMI between 30 and 39.9 kg/m2(obese classe I and II), Group III, BMI>40Kg/m2(morbid obese). Skin biomechanical behavior was assessed by the Cutometer SEM 575 (CK electronics, FRD). The chosen biomechanical descriptors were maximum extensibility Uf (R0) retraction Ua (R8) , total elasticity Ua/Uf (R2) , elastic function Ur/Ue (R5) and viscoelasticity Uv/Ue (R6) obtained in the face (zygomatic area and forehead) breast and abdomen. Statistics involved the Kruskall-wallis and the Tukey tests. Weight gain was expected to improve skin biomechanics, following skin’s adaptation to this new condition. Our results has shown a worse biomechanical performance for class I and II obese while morbid obese revealed better biomechanical performance, with values close to those found for normal BMI individuals. the “U” configuration evolution observed for these variables as a function of BMI may be a sign of a different skin’s adaptation to the new body contour, underlining the “envelope” function. Nevertheless, further studies, with a wider number of individuals comprising all classes of BMI, and more functional variables are needed to achieve the explanation for these alterations in obese and morbid obese patients.