Objective The aim of this study was to investigate the diagnostic value of combined detection of neutrophil and lymphocyte ratio (NLR),monocyte and lymphocyte ratio (MLR),platelet and lymphocyte ratio (PLR) and carcinoembryonic antigen (CEA)in patients with gastric cancer.Methods Blood routine and CEA were retrospectively collected and analyzed from 209 patients who were first admitted and admitted to Wuming Hospital of Guangxi Medical University and diagnosed with gastric cancer by postoperative pathological biopsy from January 2015 to September 2020 and 209 healthy people who underwent health checkups during the same period.ROC curve was used to analyze the diagnostic value of NLR,MLR,PLR and CEA alone and in combination for gastric cancer.In addition,the continuous variables of each index between different characteristic subgroups of gastric cancer were compared.Results The values of NLR,MLR,PLR and CEA were higher in gastric cancer patients than in healthy controls,and the differences were statistically significant(P＜0.05).The sensitivity of NLR,MLR,PLR and CEA alone in the diagnosis of gastric cancer were 37%,60%,39%,43%,and the specificity were 92%,88%,91%,78%,respectively,and the area under the ROC curve (AUC) were 0.65,0.80,0.69,0.63.The sensitivity,specificity and AUC of combined NLR,MLR,PLR and CEA increased to 69%,88.00%,0.84,respec-tively.Gastric cancer patients with distant metastasis of the tumor had higher values of NLR,MLR,PLR,and the difference was statistically significant(P＜0.05).Conclusion The combined detection of NLR,MLR,PLR and CEA has high sensitivity and specificity in the diagnosis of gastric cancer,which can improve the correct rate of diagnosis of gastric cancer,and at the same time can predict the migratory changes of the tumor,which can help the early detection and diagnosis of gastric cancer patients.