The lateral upper arm flap (LUAF) was initially described by in 1982 by Song et al. as a simple skin flap, addressing the availability of cutaneous nerves for anastomoses. Katsaros et al., reported the use of a lateral upper arm skin flap, but also considered using it as a composite graft. The LUAF for the oral and maxillofacial reconstruction has several advantages over other flaps, such as constant anatomy, good color match and texture, thin design and plasticity. There is no functional limitation in the donor arm, such as strength and extension, and donor defects can be closed primarily with a linear scar, even when a flap of up to 8 cm in width is taken. For a better understanding of LUAF as a routine reconstructive option in moderate defect of maxillofacial region, the constant anatomical findings must be learned and memorized by young doctors during the specialized training course for the Korean national board of oral and maxillofacial surgery. This article review the anatomical basis of LUAF with Korean language.