We report a case of ameloblastoma radiographically suggestive of a complication of fibro-osseous and solitary cystic lesions. A 35-year-old woman was referred to our hospital for treatment, complaining of swelling in the left premolar region of the mandible. Radiological findings indicated a mixed radiopaque and radiolucent lesion in the region of the left mandibular canine and first premolar as well as a solitary cystic lesion in the mandibular second premolar region. Following biopsy, resection of mandible was performed under general anesthesia. Histopathologic examination identified follicular-type ameloblastoma with partial desmoplastic findings. Conventional radiography and computed tomography were not useful in indicating the relationship between the mixed and solitary cystic lesions. However, magnetic resonance imaging was instrumental in elucidating this relationship.