High-grade intraepithelial neoplasia of gastric glands belongs to a kind of precancerous lesion of gastric cancer, which is a part of the tumorigenesis process. High-grade intraepithelial neoplasia of gastric glands refers to a certain degree of variability of gastric glandular tissues from normal tissues, which is mainly manifested in cell morphology and arrangement of cells. High-grade intraepithelial neoplasia of gastric glands is equivalent to severe heterogeneous hyperplasia or carcinoma in situ, and patients may experience symptoms such as epigastric discomfort, acid reflux and heartburn, etc. They should go to the hospital in time for further examination, and be treated in time through the use of medications such as omeprazole, mosapride, etc., or submucosal dissection or major gastrectomy under the guidance of doctors. Patients with gastric glandular high-grade intraepithelial neoplasia can reduce the adverse effects of the disease through early detection, early diagnosis, early treatment, many patients can be completely cured after active treatment, and it is recommended that patients establish confidence in treatment.