Dentigerous cyst is a common pathologic entity. After radicular cyst, dentigerous cysts are the most frequent odontogenic cysts diagnosed, accounting for 20% of all mandibular cysts. Typically, they are associated with impacted teeth, usually third molars. Its presentation in association with unerupted permanent second molar is very unusual and rare and very few cases have been reported in the literature. In this report, we describe the case of a pediatric patient with a dentigerous cyst in association with unerupted permanent second molar.