Regional odontodysplasia (RO) is an unusual developmental anomaly which usually affects unilateral maxillary teeth of primary or permanent dentition. It is common in females and has typical clinical, radiographical and histological findings. In the present case, an unusual type of RO has shown. The patient was a 5-year-old male and the involved tooth was the primary mandibular right central incisor. Clinical findings of yellow-brown discoloration, malformation, malposition and severe mobility of the involved tooth were detected. A "ghost-like" appearance of the tooth which is one of the typical features of the abnomality was noticed radiographically. The involved primary tooth was extracted and evaluated histologically. The histological analysis also confirmed the diagnosis of RO. In this case report, history and clinical, radiographical and histological features were discussed.