Chemotherapy, together with surgery and radiotherapy, is known as the three main therapeutic tools in the treatment of malignant tumors. At present, chemotherapy is still an irreplaceable treatment method. What should patients pay attention to in chemotherapy? First, the therapeutic effect of chemotherapy should be correctly recognized. For surgical patients, chemotherapy before or after surgery, which is called adjuvant chemotherapy, can improve the success rate of surgery and reduce the recurrence rate of gastric cancer. For advanced gastric cancer patients, chemotherapy can significantly prolong the survival period; secondly, patients have some misunderstandings about chemotherapy, believing that chemotherapy kills tumor cells and at the same time causes devastating blows to human normal system. Although chemotherapy has more side effects, most of these side effects are reversible, and most of them can be restored to normal after some medication or certain time for recovery, so patients need not worry about it; thirdly, chemotherapy patients will have digestive reactions, so during chemotherapy, they should eat some light, easy-to-digest and highly nutritious food as much as possible; fourthly, during chemotherapy, we should avoid infections because of lowered resistance, and patients should Fourth, avoid infection during chemotherapy, because the resistance is lowered, patients should try not to go out, or wear masks when they go out, and do not go to some crowded places, such as train stations, shopping malls, etc. Fifth, patients must remember to follow the doctor’s instructions, and regularly recheck the blood routine and liver function.