Lipofibromatous hamartoma is an uncommon benign tumor, usually unknown or misdiagnosed. We report the case of a 61-year-old patient presenting an acquired painful macrodactyly of the left thumb with paresthesia in the median nerve territory. Clinical examination reveals a tumefaction of the volar side of the wrist. She had a medical history of amputation of the forefinger for macrodactyly without any diagnosis. Paraclinical exploration guided us to the correct diagnosis; hypertrophic bone structures of the affected finger were detected on radiographs. The left median nerve appeared hypertrophic, with a fatty infiltration on the ultrasound exploration. These pathological findings revealed a late discovered lipofibromatous hamartoma of the median nerve, a rare entity often associated with macrodactyly and diagnosed in childhood. Therefore, we retrospectively made the same diagnosis for the amputated index finger with the analysis of her ancient paraclinical exams. Lipofibromatous hamartoma remains an obscure pathology and its treatment stays controversial.