In our study, we used single-cell RNA sequencing technology and hdWGCNA to identify psoriasis-specific CD8+ T cell subpopulations and screened psoriasis-specific CD8+ T cell signature genes, which may be used in the future to assist in the diagnosis of psoriasis and provide a theoretical basis for an in-depth understanding of the immune microenvironment of psoriasis. The gene discussed is CD8A; the disease is psoriasis.