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Propose: In vitro biomechanical properties of the skin are of important to cosmetic product development, plastic surgery, surgical practice, skin disease pathology, mechanical trauma and artificial skin design. However, complex biomechanical properties of the skin have not been fully understood so far. The literature of histology, in vitro biomechanical properties and modelling methods of the skin is reviewed to identify important problems that need to be tackled. Methods: A PubMed literature search was conducted using the terms 'skin,' 'biomechanical property,' 'damage,' 'collagen fibre,' 'viscoelastic' and 'dermis.' Relevant papers were read and analysed. Results: The histology of the skin has been studied considerably by means of optical and electron microscopies. The collagen fibre structure in the dermis has been observed with image analysis approach, and a few formulas for fibre orientation dispersion are proposed. The uniaxial, biaxial and bulge test methods were commonly applied to determine in vitro biomechanical properties of the skin. In vitro biomechanical properties exhibit nonlinear anisotropic behaviour, and at a higher strain rate, there is damage effect. Simple elongation model, isotropic model, collagen fibre recruitment model and micro-structure based model are applicable for the skin. The biomechanical property constants can be determined from the stress-stretch curves obtained in uniaxial or biaxial or multi-axial or bulge tests. Conclusions: The collagen fibre network 3D structure remain unclear and the fibre orientation dispersion characteristics are not totally understood. The damage effect in the skin has not been tackled by using constitutive laws so far. The tensile damage and fracture process, multi-layer biomechanical models developing, viscoelastic property testing and modelling in the skin should be paid significant attention in future. [ABSTRACT FROM AUTHOR]