The case presentation involves a 51-year-old male with a diagnosis of moderately differentiated keratinizing squamous cell carcinoma located in the right gingivobuccal mucosa and sulcus. Following extensive surgical resection, including right partial mandibulectomy, partial maxillectomy, and modified radical neck dissection, reconstruction was performed using kidney-shaped pectoralis major myocutaneous (PMMC) flap. This method aims to overcome the shortcomings of conventional flap designs by offering a reconstruction that is more customized and practical.