Objective:To explore the expression of ADAR1 and AZIN1 in cancer tissues and adjacent tissues of gastric cancer patients and study their clinical significance.Methods:116 patients with stage I-III gastric cancer treated in the Department of Gastroenterology and Oncology from Jan. 2020 to Jan. 2021 were recruited as research subjects. All patients were treated with surgical resection and confirmed by histopathological analysis. All patients signed the protocol informed consent upon inclusion in the study. The relationship between ADAR1 and AZIN1 expression and clinicopathological characteristics in gastric cancer tissues of patients was analyzed. The expression of ADAR1 and AZIN1 mRNA in gastric cancer and adjacent tissues was analyzed by qPCR. The expression of ADAR1 and AZIN1 in gastric cancer and adjacent tissues was analyzed by immunohistochemistry. The relationship between ADAR1, AZIN1 and patient survival rate 3 years after surgery was analyzed. Multivariable Logistic regression was used to analyze factors affecting the poor prognosis of gastric cancer patients. ROC curve was used to analyze the diagnostic performance of ADAR1 and AZIN1 expression levels in the prognosis of gastric cancer patients.Results:ADAR1 and AZIN1 had higher expression levels in undifferentiated gastric cancer tissue, patients with lymph node metastasis, and higher TNM staging, indicating that the high expression of these two genes was closely related to the malignancy of gastric cancer. QPCR analysis showed that the expression of ADAR1 mRNA in gastric cancer tissue and adjacent tissue was 1.96 ± 0.18 and 1.12 ± 0.03, respectively. The expression of AZIN1 mRNA in gastric cancer tissue and adjacent tissue was 1.85 ± 0.16 and 1.04 ± 0.02, respectively. The expression of ADAR1 mRNA in gastric cancer tissue was higher than that in adjacent tissue ( P<0.05). ADAR1 and AZIN1 positive patients were associated with lower 3-year survival rates ( P<0.05). In the multivariate logistic regression analysis of poor prognosis in gastric cancer patients, low differentiation, deepening of infiltration, lymph node metastasis, higher TNM staging, positive expression of ADAR1 and AZIN1 all significantly increased the risk of poor prognosis in gastric cancer ( P<0.05). The sensitivity and AUC value of joint detection were higher than those of ADAR1 and AZIN1 alone detection ( P<0.05) . Conclusions:The expression of ADAR1 and AZIN1 in gastric cancer tissues is significantly higher than that in para-cancerous tissues, especially in patients with undifferentiated tumors, lymph node metastasis and high TNM stage. The high expression of these two genes is closely related to the poor prognosis of gastric cancer patients, and the combined detection shows higher diagnostic efficiency. Therefore, ADAR1 and AZIN1, as key biomarkers for the development and prognosis of gastric cancer, provide new targets for gastric cancer treatment.