A 52-year-old male, with a clinical diagnosis of liver circhosis, liver tumor and gynecomastia, developed a hard mass in the left breast. Although the breast lesion at biopsy was considered to be primary breast cancer, postmortem examination revealed metastatic breast lesion originating from cholangiocarcinoma in the liver. The metastatic spread to the mammary gland was likely to have been encouraged by the presence of gynecomastia.