Horseshoe kidney is a rare form of congenital renal malformation. It occurs in 0.25 to 3% of the population and is usually asymptomatic. Occurrence of symptoms is usually related to infection, lithiasis, and rarely, malignancy. Presented is a case of a 62-year old male with a one-year history of occasional painless hematuria associated with epigastric discomfort. On physical examination, a palpable mass was noted on the right periumbilical area, 10cm x 10cm in size and was non-tender. CT-scan with IV contrast showed 10cm x 7cm x 12cm mass on the right side of a horseshoe kidney. He underwent Radical Nephrectomy, right with Isthmusectomy. Post-operative course was unremarkable. Histopathology result showed Renal Cell Cacrcinoma, clear cell type.. Although malignancy was present in an anomalous kidney, the prognosis is the same as with normal kidneys. To date, this is the first reported case of malignancy on a horseshoe kidney in the Philippines.