We identified eight negatively correlated miRNA–SFXN1 and miRNA–SFXN2 pairs, namely hsa-miR-22-3p–SFXN1, hsa-miR-140-5p–SFXN1, hsa-miR-582-3p–SFXN1, hsa-miR-532-5p–SFXN1, hsa-miR-9-5p–SFXN2, hsa-miR-34a-5p–SFXN2, hsa-miR-532-5p–SFXN2, and hsa-miR-885-5p–SFXN2, which might regulate SFXN1 and SFXN2 expression in BC and were used to explore the prognosis of BC patients. This evidence concerns the gene SFXN2 and breast cancer.