Melanoma develops from melanocytes and typically occurs on the skin and mucosa with a high degree of malignancy. Intensive local invasion and distant metastasis of melanoma result in poor patient prognosis, owing to frequent metastases to the lungs, bones, brains, and other parts of the body. In the present study, we report a case of anorectal melanoma in a 56-year-old woman who was admitted to our hospital because of local recurrence 9 months after local resection. She subsequently underwent radical surgery. Metastasis to the left breast occurred within 4 months after radical surgery. Metastasis of anorectal melanoma to the breast is very rare. In the present case report and literature review, we analyzed the clinical manifestation, diagnosis, and treatment of anorectal melanoma metastatic to the breast.