Nutritional deficiency after gastrectomy is caused by anatomical and physiologic changes in the stomach. In the case of patients with gastric cancer, nausea and loss of appetite due to cancer cachexia syndrome can affect nutritional status after gastrectomy. Prognostic nutritional index based on preoperative nutritional conditions is used for prediction of postoperative outcomes including long-term survival. Generally, enteral nutrition is more effective for post-gastrectomy conditions than parenteral nutrition. In addition, specialized enteral formulas such as immunonutrition (amino acids, ω-3 fatty acids and nucleotide) seem to have benefits for gastrectomy patients, although there is still insufficient evidence. Ghrelin is a next generation agent to stimulate appetite in patients that underwent gastrectomy.