Salivary glands include three pairs of large salivary glands (i.e. parotid, submandibular and sublingual glands) and many small salivary glands scattered in the submucosa of oral cavity. Generally speaking, among the salivary glands, parotid gland has the most tumors, accounting for 80%; submandibular gland tumors account for about 5-10%; sublingual gland tumors are less common, accounting for only about 1%; small salivary gland tumors account for about 10-15%; mixed tumors are the most common benign tumors occurring in the salivary glands. Diagnosis 1. Painless mass in the salivary gland area with slow growth. 2.The surface of the mass is smooth in small cases, but nodular in large cases, with medium hard texture, no pressure pain, and no facial paralysis. 3.Salivary gland imaging shows benign occupying lesions. 4. B-mode ultrasound shows smooth reflective images with smooth boundaries and uniform internal echogenic distribution of light spots. 5.Growth is accelerated, hardness is increased, mobility is decreased or even fixed, facial nerve paralysis, skin ulcers and other signs of malignancy. Treatment measures 1.Since the tumor site is often deeper, preoperative biopsy is generally not recommended. 2. Frozen biopsy is often needed during surgery to clarify the diagnosis. 3.Mixed tumor is a borderline tumor, and simple extraperitoneal resection often has recurrence, and multiple recurrence may be malignant, so the safety margin of surgery should be expanded appropriately. The tumor is a borderline tumor, which can become malignant after a long period of time or stimulated by inappropriate treatment. Therefore, once a mass in the salivary gland is found, it should be surgically removed in a timely manner, and it should not be treated with drugs of unknown composition. The prognosis of surgery after malignant transformation is far less than that of surgery in benign phase.