Despite the development of microsurgery, local flaps still play an essential role in the reconstruction of head and neck defects. The submandibular gland flap (SMGF) has proven to be a reliable method for repairing medium-sized defects. It requires a shorter duration of general anesthesia and has fewer donor site complications compared to the free flap. However, the restricted vascular pedicle length limits its application. Retrograde flow is one solution. The authors describe a novel technique of using reverse submandibular gland flap (RSMGF) for the reconstruction of oral cavity defects. Additional vascular pedicle length was obtained by ligating the proximal end and dissecting the distal end of the facial vessels, thus extending its application range. The RSMGF is technically feasible and suitable for repairing medium-sized defects of the oral cavity (cT2 stage tumor) like buccal mucosa, especially for the elderly in poor general condition, for whom free flaps are not applicable.