〔Abstract〕 Objective To investigate the role of squalene epoxidase(SQLE) knockout in anti-tumor effect vial improving CD8+T cell infiltration in melanoma tumor microenvironment. Methods Both immunodeficient and immunocompetent mice were inoculated withSQLEknockout B16F10 cells to determine the cell-autonomous and non-autonomous regulation of malignancy. Antibody blockade, Luminex multiplex assays, and flow cytometry were employed to explore the impact ofSQLEgene knockout on the secretion of cytokines/chemokines and immune cell infiltration. Bioinformatics analysis was conducted to validate the correlation betweenSQLEexpression and immune infiltration as well as clinical prognosis in melanoma patients. Results Compared with immunodeficient mice,SQLEknockout significantly inhibited melanoma proliferation in immunocompetent mice and prolonged their survival.SQLEknockout induced the secretion of cytokines and chemokines from tumor cells, improved CD8+T cell infiltration in the tumor microenvironment, thereby potentiating anti-tumor immunity. Bioinformatics analysis suggested a significant correlation betweenSQLEand its corresponding immune infiltration markers with the prognosis of melanoma patients. Conclusion SQLEregulates anti-tumor immunity by controlling cytokines and chemokines releasing in tumor microenvironment, thus holding promise as a novel tumor immunotherapy target and efficacy prediction molecular indicator.