Exploring the essence of general anesthesia has always been a difficult problem in related fields. In recent years, the mechanism of anesthetics acting on the central nervous system of the brain has gradually become a hotspot by using electroencephalogram (EEG). This article reviews the effects of different anesthetics on the characteristics of segmented spectrum of EEG, and their applications in the study of the mechanism of action of anesthetics on brain network and brain functional connectivity, with a view to further exploring the mechanism of action of anesthetics.