To investigate the role of the IL-17 system in adenomyosis, in our study, IL-17A and IL-17R were identified in eutopic endometrium and adenomyosis, and the fold change levels of IL-17A and IL-17R were both significantly higher in adenomyosis than in eutopic endometrium, implicating that the IL-17 system functions as a local immunomodulatory factor in adenomyosis. The gene discussed is IL17A; the disease is adenomyosis.