Objective To investigate the neural mechanism of event-based prospective memory（ PM） deficits in schizophrenia patients utilizing functional magnetic resonance imaging（ fMRI）. Methods A total of 20 healthy volunteers and 20 patients with schizophrenia were enrolled in this cross-sectional case-control study. The event-based PM tasks（ double-task paradigm， including the ongoing task and PM task） was performed as the stimulus tasks. In addition， Positive and Negative Symptom Scale and Scale for the Assessment of Negative Symptoms（ SANS） were used to assess the severity of mental symptoms， and Rating Scale for Extrapyramidal Side Effects was used to assess the severity of extrapyramidal side effects. Matlab 2011b and SPM8 software were used to preprocess and analyze the imaging data. Independent sample t-test was used to analyze and compare the activation of brain area between the two groups. The significant difference between the two groups was set as P＜0.005（ uncorrected）. In this study， REST 1.8 software was used to extract the signal intensity of blood oxygen level dependence in the brain area activated by prospective memory. Pearson correlation analysis was used to explore the related factors of activation intensity in the brain area. Results In the pretreatment， two subjects in the observation group had obvious head movement（ movement ＞2.5 mm， rotation ＞2.5°）. Excluding image analysis， 18 subjects in the observation group and 20 subjects in the control group entered the statistical analysis. Patients with schizophrenia has lower accuracy and a longer reaction time（ RT） of the PM tasks compared to healthy volunteers［ （83.40±15.33）% vs（ 94.30±10.94）%，（ 870.54±156.70）ms vs （757.33±187.44）ms； P＜ 0.05］. In addition， the RT of ongoing task was positively correlated with the SANS scores（ r=0.494，P=0.037）， and the accuracy of PM task was positively associated with IQ（ r=0.558，P=0.016）. Moreover， we found a negative relationship between the RT of PM task and chlorpromazine equivalents （r=0.492，P=0.038）. Patients showed lower activations in right middle frontal gyrus（ MFG）， bilateral inferior parietal lobe（ angular gyrus， superior marginal gyrus）， right anterior cingulate cortex（ ACC） and right precuneus while performing the task（ P ＜ 0.005）. The activations in right supramarginal gyrus（ r=-0.589，P=0.010）， left angular gyrus（ r=-0.593，P=0.010）， and right precuneus（ r=-0.590，P=0.010） was negatively correlated to chlorpromazine equivalents， and the activations in right ACC（r=-0.537，P=0.021） and right MFG（r= -0.501，P=0.034） was negatively associated with the RT of ongoing task. Conclusions Cognitive resources are consumed while performing prospective memory task. Patients with schizophrenia have significant deficits in event-based prospective memory， which may be related to the dysfunction of middle frontal cortex， inferior parietal lobule， anterior cingulate gyrus and precuneus.