The retromandibular vein is formed when the superficial temporal and maxillary veins join in the substance of the parotid gland and it descends to the angle of mandible, where it divides into an anterior and a posterior division (Fig. 8.164)—the posterior division joins the posterior auricular vein to form the external jugular vein, and the anterior division joins the facial vein to form the common facial vein, which passes deep and becomes a tributary to the internal jugular vein.