Background. Polymorphism of clinical manifestations of mental pathology in dermatology often leads to diagnostic errors and severe social exclusion of patients.Clinical case description. The presented clinical case demonstrated the similarity of the clinical picture of self-destructive dermatosis with the symptoms of pyoderma gangrenosum, which determined our differential diagnostic search. Ulcerous defects in the patient were localized in places accessible for self-destruction and did not cause severe pain characteristic of pyoderma gangrenosum. In addition, lack of association with systemic diseases, unsuccessful long-term dermatological treatment, uniformity of skin lesions, and rapid healing of skin manifestations resulting in a scar were more characteristic of self-destructive dermatosis. A pathomorphological examination of the skin revealed morphological data typical of artificial dermatitis in combination with sclerotic changes, and excluded the presence of granulomatous diseases, vasculitis, and deep purulent inflammation of the dermis (neutrophilic dermal abscesses). Thus, histological changes in the biopsy material did not correspond to the clinical skin manifestations. The constant self-destructive actions of the patient resulted in excoriations, ulcerations, with the subsequent secondary infection and conspicuous cicatricial skin changes.Conclusion. The presented clinical case demonstrated the complexity of the diagnostic search for a psychodermatological disorder due to the similarity of the clinical picture of self-destructive dermatosis with the symptoms of pyoderma gangrenosum, which led to a delayed diagnosis.