Objective <p>This study was to investigate the effects of psychological care with dietary care on the psychological state and quality of life of patients undergoing chemotherapy for advanced gastric cancer (GC).</p> Methods <p>The negative emotions, nutritional status, biochemical indicators (serum albumin, prealbumin, and hemoglobin), quality of life, chemotherapy adverse reactions, and compliance to chemotherapy of patients were evaluated between the control group (receiving routine care) and observation group (receiving routine care plus psychological as well as dietary care) of chemotherapy patients with advanced GC.</p> Results <p>The scores of Self-Assessment Scale for Anxiety (SAS), Self-Depression Scale (SDS), and Patient Generated Subjective Global Assessment (PG-SGA) were lower; levels of serum albumin, prealbumin, and hemoglobin were elevated; scores of the quality of life were higher; the incidence of adverse reactions was lower; and the compliance to chemotherapy was elevated in the observation group than those in the control group.</p> Conclusion <p>Providing psychological and dietary care to patients with advanced GC diminishes negative emotions, decreases adverse reactions, enhances nutritional status, and improves quality of life.</p> <p>Clinical trial registration: <a href="http://www.clinicaltrials.gov">www.clinicaltrials.gov</a> identifieris. ChiCTR1800120031.</p> <p>Date of registration: December 31, 2018.</p>