The dentigerous cyst, also called a follicular cyst is an odontogenic cyst that develops in association with crown of an impacted tooth, predominantly in mandibular third molars of young patients. The Odontoma is a ectomesenquimal tumor of unknown origin that are more considered developmental malformations (harmatomas) than benign neoplasms. Occasionally, the dentigerous cyst is associated with odontoma. Objective: The article aims to report a case of surgical treatment of dentigerous cyst associated with compound odontoma and unerupted tooth in anterior region of the mandible. Case report: A male patient, 17 years of age, without systemic changes, was sent to the Center for Dental Specialties of Horizonte, Ceará, Brazil, specialty of Oral and Maxillofacial Surgery, for diagnosis and treatment of oral lesions visualized after periapical radiographic examination to determine failed eruption of element 42. Observing the periapical radiograph it was possible to visualize radiopaque lesion suggestive of a compound odontoma and a cystic capsule in association with the element 42. A panoramic radiograph was requested and it was planned a surgical removal of odontoma with curettage of bone cavity and removing the cystic capsule and element 42. There were no significant postoperative complications, the suture removal was performed 7 days after surgery where it was possible to observe a good healing, no swelling and no paresthesia. Conclusion: The treatment of choice is surgical excision of the lesions with the tooth associated to the cyst, it should be performed with proper planning, avoiding injury to vital structures and should not be delayed in order to avoid possible occlusion sequelae.