This paper presents a case report of a 10-year-old child patient reported with the chief complaint of a painless, hard swelling in the lower right back region of the jaw. The clinical and radiographic examination, including intraoral periapical radiograph (IOPA) and cone-beam CT (CBCT), was performed. Conservative treatment was planned based on the clinical and radiological diagnosis of the cyst. But the histological examination revealed unicystic ameloblastoma (UA). This clinical case of UA, which was misdiagnosed as a combination of a radicular cyst and a dentigerous cyst, is being presented to highlight the importance of histopathologic investigation of all tissue specimens retrieved after surgery, particularly when the clinical and radiological findings are insignificant.