In this study multiple databases were used to explore the expression level, methylation, gene mutation, prognosis, immune infiltration, tumor stemness, related pathways and potential drugs of malignant tumors, Our main objective was to uncover the potential function of KCNQ4 using bioinformatics in various tumors and verify its potential influence on the development of breast cancer. This evidence concerns the gene KCNQ4 and breast carcinoma.