Abstract: Simultaneous EEG-fMRI integrates the complementary advantages of the high temporal resolution of EEG and the high spatial resolution of fMRI, and is a non-invasive technique for the study of human brain function. However, it remains many challenges such as low signal-to-noise ratio, poor comfort and difficulty in data fusion. On the basis of introducing the hardware of simultaneous EEG-fMRI system, wesystematically review the advance in signal processing of this technique, including the EEG artifacts correction, the EEG-fMRI data fusion, the application of EEG-fMRI and the prospects for future research. This review provides a systematic classification for the EEG-informed fMRI from simple to complex level, which may contribute to the wide application and popularization of this new technique.