Gastrin-releasing peptide (GRP) is a homolog of bombesin (BB/BN) in mammals that is distributed throughout the central nervous system. GRP is an important neuromodulator in the brain that plays an important role in various physiological functions and instinctive behaviors of animals and also can regulate the advanced functions of the brain. In the nervous system, the formation, maintenance, and extinction of animal memory are associated with GRP level, especially those related to fear and anxiety, as well as synaptic plasticity change to different degrees. GRP and its receptors are also thought to be associated with the central nervous system diseases and are potential therapeutic targets. However, the relevant mechanism has not yet been clarified, and many researchers have proposed relevant hypotheses based on different experimental methods. In this paper, we review the function of GRP and its receptors on aversive emotion-driven memory, synaptic plasticity, and the mechanism in the central nervous system from the aspects of traditional pharmacology, genetics, and electrophysiology, hoping to provide new ideas for further studies on the role of GRP system in the central nervous system.