The incidence of melanoma in US adults is approximately 1.5 per million, with 2% to 5% of patients developing metastatic disease. In children, melanoma is distinctly uncommon, and metastatic disease occurs even more seldom. This case report, the first of a patellar lesion as the initial presentation of metastatic melanoma in a pediatric patient, highlights use of patellectomy and intraoperative radiation therapy in obtaining palliative local control while avoiding periarticular functional morbidity.