A 15-year-old Indian male patient presented with a history of pain and swelling in left mandible. Imaging studies revealed a well-defined unilocular radiolucency in the body of the mandible. Patient also gave the past history of the surgery of the jaws, which was histopathologically diagnosed as dentigerous cyst. Following this patient underwent incisional biopsy and later excisional biopsy. The histopathologic diagnosis for incisional biopsy was unicystic ameloblastoma but final diagnosis was dentinogenic ghost cell tumor for the excised tissue. To the best of our knowledge, this appears o be the first case of dentigerous cyst transforming into dentinogenic ghost cell tumor. The clinical presentation of the case, differential diagnosis and treatment modalities are being discussed.