Hydradenomas, also known as nodular hydradenomas are usually rare seen cutaneous eccrine tumors. They are usually seen on the scalp, trunk and extremities. Hydradenomas occur most commonly in the adulthood. They can reach very large sizes, taking the name of giant hydradenoma which may present with tenderness and change in skin color. The differential diagnoses must include cystic hygroma, soft tissue tumors like fibroma, synovial cell sarcoma, osteochondroma and neuroblastoma metastasis in childhood. Here, a 14-year-old boy is presented with a giant clear cell hydradenoma case on the left thigh. Acoording to the furthest literature we have reached; this is the first case in which the giant clear-cell hydradenoma was reported on the thigh location in childhood.