The anterolateral thigh flap (ALTF) is a versatile fasciocutaneous or myocutaneous flap, which can be harvested incorporating several skin islands and muscle components. The perforator of the ALTF is usually derived from the descending or transverse branch of the lateral circumflex femoral artery, and these vessels are based mainly on musculocutaneous perforators traversing the vastus lateralis muscle, and also based on the septocutaneous vessels running in between the rectus femoris and vastus lateralis muscle. Despite its usefulness for the oral cavity reconstruction, anatomic variations of these nutrient vessels, such as three main branches of ALTF and its relations with sartorius, vastus lateralis, tensor fasciae latae and rectus femoris muscle, have been reconstructive surgeons to be hesitated for the selection of ALTF. For the better understanding of ALTF as a routine reconstructive procedure in oral and maxillofacial surgery, various anatomical findings must be learned and memorized by young doctors in the course of the special curriculum periods for the Korean national board of oral and maxillofacial surgery. This review article will discuss the vascular anatomy and relavant anatomical variations of ALTF with Korean language.