Acne vulgaris is a common chronic skin disease involving blockage and inflammation of pilosebaceous units. It has a genetic predisposition and sharply reduces the quality of patients’ life and the level of their social adaptation through the formation of conspicuous cosmetic defects in open areas of the skin. The processes of pathological scarring (atrophic, hypertrophic and keloid scars) is described in detail as one of the most severe consequences of acne vulgaris and its treatment. The problem is described from the modern point of view of the pathogenesis of acne vulgaris. Differential diagnosis between keloid and hypertrophic scars, as well as the most relevant approaches to classification and evaluation of severity of postacne scarring according to the valid international scales, are presented.