Objective: Based on bioinformatics, gene set enrichment analysis (GSEA) and immune infiltration analysis were carried out on the microarray data of psoriasis expression profile to further understand the pathogenesis of psoriasis. Methods: GSE6710 chip data were obtained from gene expression database (GEO), and gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis were performed using GSEA software. 22 kinds of immune cell gene expression matrices and R packages were downloaded from CIBERSOFT official website, and the immune cell infiltration matrix was obtained by R software and related graphs were drawn. Results: The pathways related to cell proliferation and innate immunity were highly expressed in psoriatic lesions, and some cancer-related pathways were highly expressed in psoriatic lesions. Immunized cell infiltration analysis showed that activated memory T cells, follicular helper T cells, M0 macrophages and activated dendritic cells were up-regulated in psoriatic skin lesion group, and inactive mast cells were down-regulated in psoriatic skin lesion group. Activated dendritic cells are positively correlated with follicular helper T cells, activated mast cells are positively correlated with M0 macrophages. Inactivated mast cells are negatively correlated with activated memory T cells, M1 macrophages are negatively correlated with regulatory T cells, M0 macrophages are negatively correlated with inactive mast cells. Conclusion: Cell proliferation and innate immunity are of great significance in the pathogenesis of psoriasis. Immune cell infiltration analysis is generally consistent with the current psoriasis pathogenesis model. Macrophages and mast cells also play a certain role in psoriasis.