The most common congenital renal fusion anomaly is the horseshoe kidney (HSK) occurring in about 1 in 600-700 individuals in the Indian population. HSKs are associated with problems such as renal stones, obstruction of uretero-pelvic junction causing stasis, and infection due to ectopic location of the kidneys, malrotation of the kidneys, and vascular changes. In general, normally developed kidneys have more incidents of renal cell carcinoma (RCC) as compared to HSKs. The major issue arises during surgery of HSK due to their altered anatomy and aberrant blood supply. We present a case of HSK with RCC located in the isthmus of a 43-year-old woman.