Introduction: Ameloblastic fibro-odontoma (AFO) is a benign complex odontogenic tumor in the mandible in children and adolescents. Observation: A 9-year-old boy was referred to the dental department for the delayed eruption of tooth 26. He was asymptomatic, and on clinical examination, we found that tooth 26 was absent with tumefaction instead of the tooth. Cone beam computed tomography revealed an opaque mass in the root of 26. The management was surgical, and anatomopathological examination facilitated the diagnosis of AFO. Commentary: The upper maxillary localization of AFO is rare and is not often a practitioner's first thought. Surgical excision of the tumor is essential based on the histological diagnosis. The patient must be followed up after 3 months and regularly until the eruption of the affected tooth. Conclusion: AFO is one of the differential diagnoses to be considered when a young patient presents with firm swelling with delayed eruption of the opposing tooth, especially since it has good prognosis and is easy to manage.