Dentigerous cyst (DCs) is the type of odontogenic cyst and is the one of the most common type of cyst occurring in the jaw. Dentigerous cyst is clinically asymptomatic and is found radiographically. It encloses the crown of impacted tooth. Histological evaluation is important in such cases as sometimes radiographically interpretated Dentigerous cyst is diagnosed as Unicystic ameloblastoma, dental follicle or an odontogenic keratocyst. In this case report, 18years old boy is reported with clinical diagnosis of pericoronitis and radiographic finding of Dentigerous cyst which on histopathological investigation revealed features of plexiform ameloblastoma on post-operative excisional biopsy.