Polymorphic adenoma is also known as a mixed tumor. It is named because it contains diverse tissues such as tumorigenic epithelium, mucus and cartilage. Myoepithelioma is a benign tumor of the salivary gland composed entirely or almost entirely of epithelial cells. The clinical manifestations and treatment of both are similar, so they are presented together. Clinical manifestations】 1. Painless masses, slow growing, often without conscious symptoms, with a long history. If it occurs in the deep lobe of the parotid gland, when it is large, it can be seen as a bulge in the side of the pharynx or soft palate, which can cause foreign body sensation in the pharynx or swallowing disorder. If the tumor grows outward, it may cause facial deformity, but generally does not cause functional disorder. When the tumor grows slowly for a period of time and then suddenly appears accelerated growth, pain or facial nerve paralysis, it indicates possible malignancy. However, some tumors have uneven growth rate and can suddenly grow faster. Therefore, we should not judge whether there is malignant change simply by the growth rate, but should consider it together with other manifestations. The tumor is spherical, lobulated or irregular, with clear circumference and medium texture, generally movable, but if it is located in the posterior jaw area and hard palate, the tumor is less movable and should not be considered as malignant. For tumors located deep in the parotid gland, dynamic enhancement scan or magnetic resonance imaging of the parotid area can clarify the location of the tumor and the relationship between the tumor and the internal jugular artery. The tumor should be removed from the normal tissue outside the tumor envelope. The tumor and superficial lobe of the parotid gland or the whole parotid gland should be resected to preserve the facial nerve. For small tumors (<1.5 cm in diameter) located in the superficial lobe of the parotid gland, a partial parotidectomy including the tumor and some of the surrounding normal glands can be performed. Tumors of the submandibular gland including the submandibular gland should be removed together. 4.Small salivary gland tumor should be resected within the normal tissue more than 0.5cm from the edge of the tumor, and the palate should be lifted from the periosteum without preserving the periosteum. If the periosteum is involved, a layer of adjacent bone tissue should be removed. For larger parotid deep lobe tumor, if necessary, the mandible should be truncated to facilitate the removal of the tumor. After the tumor is removed, the mandible is repositioned and fixed. 6.For recurrent parotid tumors, the surgical approach is discretionary. For single recurrent tumor nodule, simple tumor removal can be considered. The chance of facial nerve injury is obviously increased due to scar adhesion, so if necessary, the facial nerve should be sacrificed for immediate facial nerve defect repair.