Breast metastases from extramammary malignancies are rare. Here, we report a case of breast metastasis from hepatocellular carcinoma (HCC) after breast mass excision in a 63-year-old woman. A new breast nodule was noticed after transarterial chemoembolization, transarterial radioembolization, and stereotactic body radiation therapy for HCC. Breast ultrasound and core needle biopsy were performed to differentiate between the breast tumors. The biopsy result was invasive breast carcinoma, and wide excision of the breast was performed. The final pathological diagnosis was HCC breast metastasis based on histological findings and immunohistochemical staining results. After 9 months of follow-up, HCC and breast metastasis recurred. Despite palliative treatment, the patient died due to complications and general health deterioration. Although breast metastasis due to HCC is very rare, HCC breast metastasis should be considered when a new breast mass is discovered in a patient with a history of HCC for effective treatment and management.