Objective To examine the cognitive function of the childhood schizophrenia and healthy children,and to explore the characterized impairment of cognitive function in childhood schizophrenia.Methods Fifty untreated children with first-episode schizophrenia(schizophrenia group) and 50 healthy children(control group) were enrolled in the study.Chinese Wechsler intelligence scale for children (C-WISC),Wiscosin Cards Sorting Test (WCST),Stroop test and Trail making test A and B(TMT-A/B) were used to measure the cognitive function.The Clinical features were assessed with the scale for positive and negative syndrome(PANSS).Results Full intelligence quotient (FIQ),verbal intelligence quotient (VIQ) and performance intelligence quotient (PIQ) in schizophrenia group were significantly lower than those in the control group(P ＜ 0.05),but the change between VIQ and PIQ in schizophrenia group was higher than that in the control group(P =0.023).The complete categories in schizophrenia group were significantly lower than that in the control group(P ＜ 0.05).The total number of errors and the continuous errors in the schizophrenia group were significantly higher than those in the control group(P ＜0.05).No significant difference of the random errors was observed between the schizophrenia group and the control group.The times to complete word A,color B,double-word C and double-color D in the control group were significantly less than those in the schizophrenia group(P ＜ 0.05).The reaction time of Trail Making Test A/B and the error number of B in the schizophrenia group were significantly higher than those in the control group(P ＜ 0.05).No significant difference of the A error numbers were observed between the 2 groups (P ＞ 0.05).There were significant negative relationships between the negative syndrome and VIQ,PIQ(P ＜0.05) ;in contrast,there was significantly positive relationship between the negative syndrome and the A error numbers (P ＜ 0.05).There was significantly negative relationship between the total score of PANSS and completed categories (P ＜ 0.05).Multiple regression analysis showed that:there was a significant correlation between the damage of cognitive function in children and negative symptoms,PANSS total score,gender,age,years of education and place of residence (all P ＜ 0.05).Conclusions Children with first-episode schizophrenia have multiple cognitive deficits in speed of processing working memory,spatial memory,attention and executive function.Some of the cognitive impairments have certain relationships with negative syndrome.