Melon face surgery, or V-shaped face surgery, is performed by jaw angle osteotomy with chinoplasty to bring the contour of the jaw close to the mold of the V shape. Theoretically, an intraoral incision, a skin incision at the lower edge of the mandibular angle, and an incision in front of and behind the ear can be used. Only with the intraoral incision, there will be no surgical scars left on the surface of the facial skin. However, if the medical personnel do not strictly comply with the norms of the surgical process, the following complications may occur: 1, asymmetric deformity: osteotomy surgery if there is no good retracting instruments or similar endoscopic assistive devices, the surgical field can not be well exposed. So sometimes it will cause asymmetry after surgery on both sides. 2, hematoma: the most likely cause of hematoma after surgery is intraoperative damage to the inferior alveolar neurovascular bundle and intraocclusal blood vessels or facial blood vessels penetrating near the angle of the lower jaw. Once found, should be immediately filled with gelatin sponge and compression hemostasis, bleeding control to adjust the position or direction of the osteotomy line, postoperative retention of closed drainage, compression bandage, close observation of the drainage flow; 3, crooked corners of the mouth: some patients appear in the postoperative crooked corners of the mouth on the one side of the situation, mainly caused by the two sides of the pulling damage to the muscles, or facial nerve injury. However, most of the symptoms will be relieved or disappear after the facial swelling subsides; 4, perioral skin and mucous membrane injury: due to the pulling and compression of the pulling hook or chainsaw burning, the skin and mucous membrane around the corners of the mouth are damaged, which causes pain in the corners of the mouth; 5, infection: the most common cause of infection is secondary to hematoma, therefore, preventing the formation of hematoma is the key to preventing postoperative infections; 6, limited mouth opening: some patients still complained that their mouths do not open much even after the swelling subsided, which may be due to the loss of attachment point of the biting muscle. This may be caused by the loss of attachment point of biting muscle, resulting in masticatory muscle group power balance imbalance; 7, mandibular ascending branch injury: it can lead to the destruction of the mandibular joint, and it is difficult to open the mouth; 8, upper respiratory obstruction: due to the hemorrhage, the blood is inhaled into the trachea, and the life-threatening situation occurs. This is a serious complication; 9, hemorrhagic shock: mainly caused by injury to large blood vessels.