Objective To evaluate cognitive function in first--episode schizophrenic patients and their parents,and to explore whether the event--related potentials is the genetic or the state markers in schizophrenia. Methods Sixty patients with schizophrenia were consecutively recruited from the inpatients of the Department of Psychiatry,Xu Zhou City People,s Hospital of Eastern. They all met CCMD --3 criteria for schizophrenia. One hundred and twenty parents of the schizophrenic patients were consecutively recruited as relative group. Sixty healthy control subjects with no individual and familial history of mental illness were also recruited. The event--related potentials of them were examined respectively. All data were statistically analyzed by SPSS13.0 software. Chi-square test and analysis of variance and covariance were used to compare the eventrelated potentials among the three groups. Results （1） The N2,N3 latency and P3 latency of the patient group, relative group and the control group were all significantly different from each other （P 〈 0.01）. （2） The patient group was significant- ly different from the control group in N2 latency （P ~ 0.01）. The relative group had no significant difference from control group in the latency （P〈 0.05）. The amplitude P3 of the patients and relatives were both significantly different from the control group （P 〈 0.01）. The patient group was not different from the relative group in the P3 amplitude （P 〉 0. 05）. Conclusions The study supported the following points： （1）Both first--episode schizophrenic patients and their parents had defect in their functional recognition. （2）The P3 amplitude was possibly the genetic marker of schizophrenia,and the N2 latency was possibly the state marker of the schizophrenia.