Reconstruction following a resection of malignant oral cavity tumors is one of the most difficult problems in recent oral oncology. The radial forearm free flap (RFFF) is a thin, pliable soft tissue flap with large-caliber vessels for microvascular anastomosis. Its additional advantages include consistent flap vascular anatomy, acceptable donor site morbidity and the ability to perform simultaneous flap harvest with a tumor resection. For a better understanding of RFFF as a routine reconstructive procedure in oral and maxillofacial surgery, the constant anatomical findings must be learned and memorized by young doctors during the special curriculum periods for the Korean national board of oral and maxillofacial surgery. This review article discusses the anatomical basis of RFFF in the Korean language.