The ferroptosis genes associated with dermatomyositis are mined by bioinformatics to provide a new idea for clinical diagnosis and treatment of dermatomyositis. The dataset about dermatomyositis was screened from the comprehensive gene expression database, and the dataset was analyzed using R language. 261 differential genes of dermatomyositis were obtained, and 15 ferroptosis genes related to dermatomyositis were obtained after intersection with ferroptosis genes in FerrDb database. According to the Kyoto Encyclopedia of Genes and Genomes pathway, its role may be related to inflammation, ferroptosis, oxidative stress, and apoptosis. Based on protein-protein interaction network analysis and Cytoscape selected five key genes associated with dermatitis and ferroptosis. The potential of four diagnostic genes TIMP1, HMOX1, TFRC and CDK1A as biomarkers for the diagnosis and treatment of dermatomyositis is further identified through gene expression and receptor working characteristic curves, providing new insights into the mechanism of ferroptosis in dermatomyositis.