Abstract: Objective：To explore the characteristics of clinical symptoms and intelligence quotient in adolescents-onset and youth-onset schizophrenia. Methods：Forty-one cases with adolescents-onset schizophrenia(adolescents group) and 98 cases with youth-onset schizophrenia (youth group) were tested by the self-made general condition questionnaire, the assessment of positive symptoms(SAPS), the assessment of negative symptoms(SANS), Wechsler child intelligence scale or Wechsler adult intelligence scale-revised in China. Results：①There were difference about the course and the history of the family between adolescents group and youth group(P≤0.01). There were no difference about the scores of SAPS and SANS between adolescents group and youth group(P>0.05).②The scores of the full intelligence quotient(FIQ)，the verbal intelligence quotient(VIQ)and the performance intelligence quotient(PIQ) of all cases were more than seventy, there were no difference about the scores of FIQ,VIQ and PIQ between adolescents group and youth group(P>0.05).Conclusions：The cases with adolescents-onset and youth-onset schizophrenia were with chronic course, there were similar about clinical symptoms and intelligence, but the course of adolescents-onset schizophrenia group was relatively short, positive rate of family history was relatively high.