Objective To identify the gene co-expression modules and hub genes of obsessivecompulsive disorder （OCD） through weighted gene co-expression network analysis （WGCNA） of gene expression profiles. Methods The GSE60190 dataset was downloaded from the Gene Expression Database （GEO）. The gene expression data from the dorsolateral prefrontal cortex （DLPFC） of postmortem brain of 15 OCD patients and 14 healthy controls were used to detected the co-expression module related to OCD. The co-expression modules related to OCD were identified by WGCNA. GO enrichment analysis was performed on key modules related to OCD by Metascape database. Protein-protein interaction （PPI） networks for key modules were constructed through STRING database. CytoHubba in Cytoscape was used to identify hub gene candidates. Results A total of 9 co-expression modules of OCD genes were identified， with module characteristic gene values ranging from 168 to 2 676. The green module （MEgreen） was positively correlated with OCD （r=0.52， Pcorrected=0.036）. The enrichment analysis results showed that MEgreen involves multiple biological processes （BPs）， including response to steroid hormones， response to ionizing radiation， regulation of reactive oxygen species biosynthesis process， regulation of striated muscle cell differentiation， regulation of ATPase activity， "de novo" protein folding， protein import， and microtubule cytoskeletal organization. PSMD12， PSMD1， CDKN1B， CDC34，SRSF1， and CCT2 were identified as hub genes that might be associated with the development of OCD. Conclusions MEgreen and six genes， including PSMD12， PSMD1， CDKN1B， CDC34， SRSF1， and CCT2， may play a certain role in the occurrence and development of obsessive-compulsive disorder through ubiquitin system， cell cycle， stress response， and steroid hormone response.