A comparative clinical-epidemiological study was made in groups of schizophrenics with onset in adolescence hospitalized for the first time at the Regional Tomsk Mental Hospital in 1948-1951 (period I), in 1958-1961 (period II), in 1968-1971 (period III) and in 1978-1981 (period IV). A primary hospitalization rate in patients with adolescent schizophrenia has been stable for the last 30 years. In general population of schizophrenics hospitalized for the first time, a reliable proportional reduction of adolescent schizophrenics from the first till consequent periods (from 31.1% till 17.7%) was observed. Group I patients show reliable differences by severity of psychopathological disorders and lower level of socio-occupational adaptation in comparison with the other groups. According to 6-year follow-up data, clinical and socio-occupational characteristics of the patients show more frequent dissociation between clinical and social levels of adaptation which in half of the cases is manifested by low level of socio-occupational adaptation.