Kaplan–Meier survival analysis showed that FOXP3 and CCL20 expression in tumors were strongly correlated with unfavorable prognostic factors in breast cancer patients’ cohort, the patients with the concomitant CCL20 high expression and increased FOXP3+ TILs infiltration showed the worst OS and DFS than those with CCL20 low expression and/or low FOXP3+ TILs. The gene discussed is CCL20; the disease is breast cancer.