Intestinal microbes have an adjuvant therapeutic effect on neurological disorders (such as Parkinson’s, depression, and Alzheimer’s disease). It affects brain function and host behavior through the neural pathways, the immune pathways and the microbial metabolites, the so-called gut-brain axis. This article summarizes the recent advances in the role of the microbe-gut-brain axis in neurological disorders, in order to provide new ideas for the treatment of neurodegenerative diseases.