The 5-year survival rate after treatment for progressive gastric cancer is generally 20%-50%, and the mortality rate is second only to lung and liver cancers. There is an initial consensus in gastric cancer surgery that surgery alone cannot achieve biologically meaningful cure, even with extended resection and lymph node dissection. Therefore, it has become a goal to improve the prognosis of patients with gastric cancer by actively seeking possible means to cure the tumor and increasing the surgical resection rate, especially the radical resection rate. In recent years, the application of neoadjuvant chemotherapy, or preoperative chemotherapy, in gastric cancer patients has gradually become a hope and research hotspot for the treatment of progressive gastric cancer. Xie Jianguo, Department of General Surgery, Henan Cancer Hospital, China Neoadjuvant chemotherapy is introduced: surgical resection is the only possible means to cure gastric cancer, and the 5-year survival rate after surgery can reach 85%-95% for stage I gastric cancer limited to early lesions. Only 10%~11.5% of gastric cancer patients in China are early stage gastric cancer. The 5-year survival rate after surgery for progressive gastric cancer is generally 30%~50%, and mostly does not exceed 60%. An initial consensus has been reached that surgery alone cannot achieve biologically meaningful radical cure, including extended resection and lymph node dissection. Therefore, aggressively seeking other means of possible tumor eradication and increasing the rate of radical resection become the means to improve the prognosis of gastric cancer. The use of certain preoperative measures to shrink the lesion of progressive gastric cancer and reduce the invasion of the tumor and its affiliated lymph nodes to the surrounding organs is a direction of effort and the original purpose of the emergence of neoadjuvant chemotherapy. The rationale of neoadjuvant chemotherapy is: (1) surgical removal of the primary tumor may stimulate the growth of the remaining tumor cells; (2) postoperative changes in blood flow in the tumor surrounding tissues affect the concentration and effect of chemotherapeutic agents; (3) the purpose of stage reduction can be achieved to improve the surgical resection rate; (4) the possibility of intraoperative dissemination is reduced and the activity of tumor cells is decreased; (5) potential micrometastases are eliminated and the possibility of postoperative metastatic recurrence is reduced (6) to accurately determine the clinical remission rate through measurable lesions and postoperative specimens before surgery; (7) neoadjuvant therapy can eliminate patients who are not suitable for surgical treatment, and some gastric cancers with poor biological behavior can progress rapidly and develop extensive local infiltration and distant metastases during adjuvant therapy; (8) to understand the tumor response to treatment through preoperative adjuvant chemotherapy to determine whether patients need to continue treatment after surgery. The currently accepted principles of application of neoadjuvant therapy for gastric cancer are locally progressive cancers that may be radically resected, with the aim of controlling microscopic metastases in people with high risk of recurrence. Significance: (1) Preoperative chemotherapy can reduce tumor load to different degrees, reduce tissue reactive edema, shrink the tumor and make the clinical stage lower. (2) To improve the rate of curative surgical resection and reduce the recurrence rate; (3) To control the preoperative presence of microscopic cancer foci and subclinical foci, inhibit the stimulation of tumor proliferation triggered by the action of surgery, and have a certain killing effect on microscopic lesions; (4) To control medical metastasis, administer chemotherapy before the vascular supply and lymphatic vessels of tumor lesions are damaged, which can easily make the tumor localize to an effective concentration and play a high-dose (5) To obtain in vivo drug sensitivity information of tumor, which can provide a basis for postoperative determination or selection of adjuvant chemotherapy regimen; (6) Early chemotherapy can prevent distant metastasis; (7) To avoid unnecessary surgery for those with rapidly progressing tumor. Timing of neoadjuvant chemotherapy surgery: The significance of neoadjuvant chemotherapy is to seek to improve the prognosis for cases with radical resection, and the other is to seek radical resection for cases that cannot be radically resected. The timing of surgery presupposes exact clinical staging. It depends mainly on imaging methods, such as CT, MRI. The toxic efficacy of drugs, protocols and histological effects should also be considered together. Normal white blood cells and platelets should be met 14 days prior to surgery. Surgery is the only effective way to treat gastric cancer. However, the surgeon should choose the surgical option according to the patient’s interest, not just surgery for the sake of surgery. It must break the view of pure surgery to effectively prolong the patient’s life and achieve a cure.