Oral cancer refers to malignant tumors that occur in the oral cavity and its adjacent anatomical structures, and is one of the more common malignant tumors of the head and neck, accounting for about 3% of the malignant tumors in the whole body, and oral cancer used to take the sixth place among the deaths caused by cancer in Europe and America. The incidence rate of oral cancer is slowly decreasing in some developed countries, but worldwide, the incidence rate of oral cancer is gradually increasing, and its incidence rate increases with age. About 90% of oral cancers occur in people over 40 years old, and the average age at diagnosis is 65 years old. Men are more likely to develop malignant tumors than women, but there is a trend of increasing female patients. The pathological types of oral cancer can be squamous carcinoma, adenogenic carcinoma and so on, among which squamous cell carcinoma accounts for 90% of oral cancer. Oral mucosal squamous carcinoma originates from the basal cell layer of oral mucosa. Most oral mucosal squamous carcinomas start as superficial oral ulcers, and then directly invade deep tissue structures. Cervical lymph node metastasis is the main metastatic mode of oral squamous carcinoma, and it has an important impact on the prognosis. Cervical lymph node metastasis of oral squamous carcinoma is influenced by many factors, including clinicopathological factors of the tumor, metastasis-related genes and immune status of the host, etc. Among the more important clinicopathological factors of the tumor, the nature, site, size, differentiation degree and infiltration mode of the tumor are all factors to be considered. Primary tumors in some parts of the oral cavity have a higher rate of cervical lymph node metastasis than primary tumors in other parts of the oral cavity, and thus have a worse prognosis. For example, the risk of cervical lymph node metastasis in primary tumors of the tongue and floor of the mouth is greater than that in hard palate and maxillary gingival cancers of the same clinical stage. Some studies suggest that the degree of tumor infiltration is a high factor for cervical lymph node metastasis. The rate of cervical lymph node metastasis in oral squamous carcinoma ranges from 50% to 59%. Although the cervical lymphatic system is complex and there is extensive traffic anastomosis between parallel lymphatic drainage systems, which makes the lymph node metastasis of oral squamous carcinoma may appear “jump” metastasis, especially for tongue carcinoma, there is still a certain pattern in the mode and distribution of cervical lymph node metastasis of oral squamous carcinoma. It has been shown that the lymph node metastasis of oral cancer mainly occurred in regions Ⅰ, Ⅱ and Ⅲ. Among 192 cases of oral cancer selective neck clearance, only 6 cases of Ⅳ cervical lymph node metastasis were found, while “jumping metastasis”, i.e., the metastatic lymph nodes went directly to region Ⅳ, while the lymph nodes in regions Ⅰ, Ⅱ and Ⅲ were negative. The number of jumping metastases directly appearing in zone IV and V was less than 10%. The goals of oral cancer treatment are to eradicate the tumor, preserve or repair the form and function, and prevent multiple primary tumors. Surgery, radiotherapy and chemotherapy are the main methods of treatment for oral squamous carcinoma, while the choice of treatment for oral squamous carcinoma mainly considers the clinical correlates of the primary tumor and the physical condition of the patient. Both surgery and radiotherapy can be applied to the treatment of oral cancer alone or in combination. The prognosis of oral cancer treated with chemotherapy is still in the research and observation stage. The selection of specific treatment usually takes into account the primary site of the tumor, its location in the oral cavity, stage, cervical lymph node metastasis, in addition to the complications associated with the treatment, cost, convenience, patient compliance and long-term efficacy of the treatment in the context of the patient’s general condition. For early oral cancer (T1 and T2), both surgical resection and radiotherapy can achieve good therapeutic results, and it is currently considered best to eradicate the tumor with a single treatment method. Surgical treatment for early oral cancer has little damage to patients and almost no long-term complications; therefore, unless there are obvious contraindications to surgery, surgical resection is the first and best method to treat most early oral cancers. In other words, it is difficult to have a satisfactory long-term survival rate with single surgery or radiation therapy. A reasonable combination of surgery, radiation therapy, chemotherapy and targeted therapy is needed to achieve individualized and optimal treatment. The usual treatment plan is surgical resection combined with postoperative radiotherapy (or radiotherapy) to improve the cure and survival rate of patients.