ObjectiveTo study the clinical significance of prognostic nutritional index (PNI) combined with neutrophil to lymphocyte ratio (NLR) in predicting the occurrence of anastomotic leakage after radical gastrectomy for gastric cancer.MethodsTo retrospectively analyze and collect the clinical data of 517 patients with gastric cancer who were diagnosed at the Third People’s Hospital of Shangqiu City from January 2016 to May 2020, all of the patients received radical gastrectomy. We explored the risk factors that affect the occurrence of postoperative anastomotic leakage, and explored the clinical significance of PNI combined with NLR on the third day after operation in predicting the occurrence of anastomotic leakage.ResultsAmong 517 patients undergoing radical gastrectomy, 61 had anastomotic leakage, and the incidence of anastomotic leakage was 11.8%. The results of multivariate logistic regression analysis showed that patients with preoperative diabetes and intraoperative blood loss ≥400 mL had a higher incidence of anastomotic leakage, and with the increase of NLR value on the 3rd and 5th day after operation, and the decrease of PNI value on the 3rd and 5th day after operation, the incidence of anastomotic leakage increased (P<0.05). The area under the curve of NLR, PNI, and NLR combined with PNI on the 3rd day after operation in predicting the occurrence of anastomotic leakage were 0.849, 0.581, and 0.949, respectively, and the differences were statistically significant (P<0.05), the sensitivity and specificity of NLR combined with PNI were higher than the individual indicator.ConclusionPNI combined with NLR on the 3rd day after operation has important clinical significance in predicting the occurrence of anastomotic leakage after radical gastrectomy for gastric cancer.