Aim. The aim of the study and was the assessment of Cognitive Remediation Therapy (CRT) in an adolescent anorexia nervosa patient. Methods. CRT cognitive training was performed. Eating Attitudes Test 26 (EAT - 26), Beck Depression Inwentory (BDI), Child Yale - Brown Obsessive - Compulsive Scale (CY - BOCS), Eating Disorders Belief Questionnaire (EDBQ), Wisconsin Card Sorting Test (WCST), Temperament and Character Inventory, (TCI) and also Child Heath Questionnaire (CHQ) - assessed by parents, were used before and after the programme. Results. After CRT completion, an improvement on the level of psychopathological symptoms was observed (especially in the EAT - 26 and 13131 scales), in WCST some improvement was noticed. In TCI, no significant changes were found. In comparison to the initial assessment, an increased level of dysfunctional beliefs was observed. Conclusions. Cognitive Remediation Therapy can be used in adolescent patients with anorexia nervosa. This procedure may be related to cognitive and symptomatological improvement.