Coronavirus is a new virus that has affected human life on a large scale; it has infected millions of people and killed hundreds of thousands of people. In contrast, among cancers, stomach neoplasia is the most common cancer of the upper gastrointestinal (UGI) tract. COVID-19 disease has disrupted the optimal management of patients with cancer. Metastasis, deterioration of the patient’s nutritional status, UGI bleeding, and increased surgical complications are all consequences of delayed treatment of patients with gastric cancer. However, there is still insufficient evidence on the immunogenicity of the vaccine and the protection provided by coronavirus vaccines in patients with cancer, especially those with immunodeficiency or those who are treated for certain types of cancers. Also, as part of the prevention and control of COVID-19 disease, nutritional support for patients with gastrointestinal cancer is particularly important, and the psychological and physiological limitations caused by the disease duration are hurting the well-being of patients. Therefore, the assessment of the impact of the coronavirus on cancer should be treated as an important issue, and healthcare professionals should be prepared to deal with the long-term effects of the coronavirus disease.