Odontogenic keratocysts are odontogenic epithelial-originated developmental cysts characterized by minimal expansion, high recurrence rate, and aggressive nature. They are usually asymptomatic and detected in routine dental examinations so can be overlooked until the lesions reach large sizes. The treatment of odontogenic keratocyst is controversial, and there are various surgical approaches ranging from conservative approaches to more invasive procedures. In this case report, a 16-year-old female patient with an enlarged odontogenic keratocyst associated with an impacted third molar and extending through the mandibular angle, ramus, and coronoid process regions is presented with the clinical, radiological, and histopathological findings and the surgical treatment plan.