OBJECTIVE Clarification of the phenomenology and dynamics of initial mental disorders in patients with psychotic pubertal forms of schizophrenia, identification of the features of these disorders depending on sex. METHODS The study material was adolescent patients with psychotic forms of schizophrenia. Forty-three people were examined (women 44.2%, median age 14.3 [13.0; 16.8] years). Clinical-anamnestic, clinical-psychopathological, clinical-statistical methods were used. RESULTS The duration of the initial stage of the disease ranged from several hours to 5 years (median 0.8 [0.5; 1.7]. The structure of initial disorders was dominated by nonspecific mental disorders characterized by a combination of symptoms of non-psychotic and subpsychotic levels (20 patients - 43.5%; including 12 males - 26% and 8 females - 24.1% ). If behavioral disorders and episodes of psychoactive substance use were significantly more often detected in boys, then dysmorphic phenomena were detected in girls (p<0.05). In accordance with the dynamics of development, acute (n=14 - 32%), subacute (n=21 - 49%), fluctuating (n=8 - 19%) variants of initial disorders are distinguished. Young men turned to a psychiatrist in a more timely manner (already at the stage of prodrome), while girls sought psychiatric help only at the stage of development of psychotic disorders. CONCLUSIONS A psychotic episode in adolescents suffering from schizophrenia developed acutely in a third of cases. In the vast majority of cases, the initial mental disorders that appeared on the eve of acute psychosis was subacute, or differed in a fluctuating course, characterized by clinical polymorphism and multidirectionality. Differences were revealed in the preference for the occurrence of a number of initial disorders in boys and girls, as well as in the timeliness of seeking psychiatric help.