Objective To analyze the correlation between resting-state electroencephalogram (EEG) microstate characteristics and cognitive function in schizophrenia (SCZ). Methods Eighty patients with SCZ admitted to Kaifeng Fifth People’s Hospital from January 2023 to October 2025 were selected as the SCZ group, and another 80 healthy controls with matched demographic data enrolled during the same period were included as the control group. Resting-state EEG signals were collected from all subjects, and the EEG microstate characteristics of four types, namely Type A, Type B, Type C and Type D, were compared. The cognitive function assessment was conducted using the Chinese brief cognitive test (C-BCT) and the Montreal cognitive assessment scale (MoCA). And the C-BCT total scores, scores on each subtest, and MoCA total scores between the two groups were compared. Pearson correlation analysis was used to explore the correlation between the EEG microstate parameters of the SCZ group and the total score of C-BCT, as well as the scores on each subtest and MoCA total scores. Results The average duration, time coverage rate and occurrence frequency of microstate C in the SCZ group were all higher than those in the control group (all P＜0.05); while the above characteristic parameters of microstate D in the SCZ group were significantly lower than those in the control group (all P＜0.01). The C-BCT total scores, scores on each subtest, and MoCA total scores in the SCZ group were all significantly lower than those in the control group (all P＜0.001). Pearson correlation analysis showed that the average duration of microstate C was significantly negatively correlated with the total score of C-BCT and the total score of MoCA (r＝?0.42, ?0.38, all P＜0.001). The time coverage rate of microstate D was significantly positively correlated with the total score of C-BCT and the score of the working memory test (r＝0.31, 0.35, P＝0.005, 0.002). The occurrence frequency of microstate C was significantly negatively correlated with the score of attention (d"" value of the sustained operation test) (r＝?0.29, P＝ 0.009). Conclusion Patients with SCZ exhibit specific abnormal changes in resting-state EEG microstate, and this abnormal pattern is closely related to the degree of cognitive impairment.