Periosteal osteoma is a rare benign pathologic lesion in the jaws and the mandible is the anatomic region most frequently involved. Elective treatment consists of surgical excision. The aim of this report was to report a rare case of bilateral periosteal osteoma involving the mandible—a painless, firm, and well-circumscribed lesion, with more bony prominence on the left than on the right side. The patient had no history of facial trauma or systemic changes that could intervene with the progression of the lesion. It was diagnosed as a periosteal osteoma, and surgical excision was performed. No recurrence after 4 years of follow-up was demonstrated. Surgical excision of the periosteal osteoma was demonstrated to be a useful technical strategy that simplifies and accelerates the surgical procedures and probably contributes to establish harmony of the jaws. Periodical clinical and radiographic follow-ups after surgery are advised.