Schizophrenia is a chronic disease. It is characterized by symptoms such as impaired behavior and cognitive ability, which seriously affects normal human activities. This study used electroencephalogram (EEG) data from 14 schizophrenia patients and 14 healthy controls to assess the casuals flow between different brain regions. First, preprocessing and source analysis was performed on the collected EEG signals. Then, the effective brain network was constructed based on the complex network theory, which is a directed network. Finally, the topological properties of the effective brain network were analyzed. It is found that the causal flow in the frontal pole, frontal, temporal and posterior temporal regions of patients with schizophrenia is different from that of the normal controls.