The objective of the present study was to elucidate the detailed morphological picture of stab injuries taking into consideration the design of the piercing objects, conditions of wound infliction, and properties of the affected tissues. The experimental injuries were inflicted either by an impact action or compression at an angle of 90 and 45-60 degrees using sharp (0.01 mm) and blunt (0.5 mm) piercing cylinder-conical bevel-edged (40 mm) objects 7 mm in diameter. A total of 128 skin injuries were available for the examination. It was shown that the shape, length, and orientation of the wounds depended on the sharpness of the injurious agent, the angle at which and the speed with which it was stabbed into the tissue. The new morphological features were identified associated with plastic deformation of the skin, viz. the shape of the wound opening, smoothness or borderline thickening of its edges, flattening and folding of epidermis; conditions for the formation of these features were investigated. These data are of importance for the individual and intra-group expert identification of the putative traumatic agents and reconstruction of the circumstances of a given event or offence.