Parotid tumors are a common disorder, of which benign tumors account for about 70% and malignant tumors account for about 30%. Among benign tumors, 80% are mixed tumors of the parotid gland, some of which may become cancerous. Patients with parotid tumors are often seen by accidental discovery of a lump around the earlobe, usually without pain and numbness. Benign tumors grow slowly, while malignant tumors grow faster; when a tumor that originally grew slowly or not significantly grows suddenly grows faster, the possibility of malignant transformation of benign tumors should be considered, just like the case encountered by Lao Zhang. When malignant tumor involves facial nerve, facial palsy may appear, manifested as eyelid closure, mouth opening and jaw skewing to the healthy side, inability to whistle and so on. In most cases, the nature of the pathology can be clarified preoperatively by using a fine needle to puncture the mass. Parotid tumors generally require surgical excision. The parotid gland is the largest salivary gland in the body, located around the earlobes on both sides of the face, and is divided into two lobes. The facial nerve is the VIIIth pair of cranial nerves in the human body, which comes out of the skull through the temporal bone and enters the parotid gland, and then enters the facial expression muscle through the anterior edge of the parotid gland to govern its movement. When the peripheral branch of facial nerve is damaged for various reasons, it will show the inability to close the eyes, open the mouth and lower jaw, puff the cheeks, and disappear the nasolabial fold. There are three aspects of parotid tumor surgery that require special attention: 1) complete removal of the tumor, 2) preservation of the facial nerve integrity (including anatomy and function), and 3) postoperative appearance. With the use of a nerve monitor, the surgeon can successfully find the facial nerve and protect it anatomically during surgery, thus minimizing the chance of facial nerve injury. Recently, it has been reported in the literature that the injury rate of the important branches of the facial nerve in benign parotidectomy without facial nerve monitoring ranges from 40% (superficial parotidectomy) to 67% (total parotidectomy), and nearly 80% in recurrent parotidectomy or parotidectomy for malignant tumors. For parotid surgery with facial nerve monitoring, the intraoperative injury rate of facial nerve in experienced hospitals is less than 1%. Although the tumor was malignant and all the parotid glands were removed, the facial nerve was preserved and the facial nerve functioned well after surgery. In addition to significantly reducing facial nerve injury, facial nerve monitoring during parotid surgery can also make the surgical incision as short and concealed as possible. Depending on the size, nature and location of the tumor, the surgeon can use incisions of different lengths and locations to achieve clean removal of the tumor while preserving part of the parotid gland and improving postoperative appearance as much as possible. Although the surgical incision is small, it is not difficult to find the facial nerve and protect it from damage with the help of facial nerve monitor.