Background: Reproductive tract sarcomas metastasizing to the breast are uncommon. To our knowledge, metastasis of vaginal leiomyosarcoma to the breast has not been previously reported in the literature. Case Report: We present the first report of a FIGO stage IV primary vaginal leiomyosarcoma with metastases to the lung and left breast. Treatment included neoadjuvant chemotherapy followed by surgery and postoperative chemotherapy. Lung metastasis disappeared but recurred 14 months later in conjunction with left breast metastasis which was resected. Conclusion: Primary vaginal sarcoma with lung and breast metastases is very rare in female genital malignancies. We present this case to alert gynecologists to the need for early diagnosis and aggressive management.