Masseter hypertrophy (MH) is one of the uncommon conditions that swelling can be seen in the angular mandibular region of the face. The etiology of MH includes several factors, and various treatment methods are mentioned in the literature. Botulinum toxin type A application is most commonly used for the treatment because of its less invasive feature. As a surgical method, some treatment alternatives that aim to reduce muscle mass or reshape the bone tissue in the angular region are considered. In this case report, a 21-year-old male patient with unilateral masseter hypertrophy on the right side is presented. After the patient was diagnosed with MH, botulinum toxin treatment in two sessions at one-month intervals was done. Since the reduction in muscle volume was not in satisfactory dimensions after the botulinum toxin application, the masseter was reduced on the right side through an intraoral approach. At the same time, bone enlargements on each side of the angulus mandibula were reshaped and smoothened through an extraoral retro mandibular approach. Clinical and radiographic evaluation of the patient revealed more aesthetic and symmetrical appearance in the regular controls.