Obsessive-compulsive disorder(OCD) is a highly disabling mental illness characterized primarily by unnecessary compulsive thinking and behavior. In terms of genetics, abnormalities in the functions of the serotonin, glutamate, and dopaminergic systems in the central nervous system, as well as abnormalities in biological processes such as inflammation and intracellular signal transduction, may be related to the occurrence and development of obsessive-compulsive disorder. Single nucleotide polymorphism may be an important reason for these abnormalities at the molecular biology level. Therefore, studying the polymorphisms of popular candidate genes in different pathogenesis mechanisms is crucial for analyzing the pathogenesis of obsessive-compulsive disorder, and there is potential in predicting risk factors and accurate treatment of obsessive-compulsive disorder.