Abstract: Gamma-aminobutyric acid (GABA), also known as 4-aminobutyric acid, is a neuromitter widely existing in organisms, but it plays different roles in different species. In animals, GABA mainly acts as an inhibitory neurotransmitter, which has sedative effect on the brain and can reduce the blood pressure of animals. In the process of plant growth and development, it plays a role in enhancing resistance. GABA can improve the resistance of microbial population and the germination rate of its spores. How to improve the content of GABA in plants has become the focus of current research. In this paper, the biological functions and metabolic pathways of GABA were summarized, which provided a theoretical basis for the further study of GABA in plants.