Salivary glands include three pairs of major salivary glands (i.e., parotid, submandibular and sublingual glands) and many minor salivary glands scattered under the oral mucosa. 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, only about 1%; minor salivary gland tumors account for about 10-15%; mixed tumors are the most common benign tumors occurring in the salivary glands. Diagnosis 1. Painless lump in the salivary gland area with slow growth. 2.Smooth surface of small lumps, nodular in large ones, medium hard texture, no pressure pain, activity (in palatine glands, it may be inactive), no facial paralysis. 3.Salivary gland imaging showed benign occupying lesion. 4, Ultrasound shows smooth reflection image, internal echo wave distribution of light spots uniform. 5. Signs of malignant changes such as accelerated growth, increased hardness, decreased mobility or even fixation, facial nerve paralysis, and skin ulceration. Treatment measures 1. Because the tumor site is often deep, preoperative biopsy is generally not suitable. 2. Frozen biopsy is often needed during surgery to make a clear diagnosis. 3.Mixed tumors are critical tumors, simple extraperitoneal resection often has recurrence, and repeated recurrence may be malignant, so the safety margin of surgery should be enlarged appropriately. 4.Mixed tumor of salivary glands should be treated by surgery. Since this tumor is a critical tumor, it can cause malignant transformation after too long survival time or inappropriate treatment and stimulation, therefore, once a mass in salivary glands is found, it should be resected by surgery in time, and it is forbidden to use the external treatment of some drugs of unknown composition. The prognosis of surgery after malignant transformation is far less good than that of surgery in benign period.