Abstract: ob＜x＞jective To investigate the relationship between intestinal mucosal barrier dysfunction and ischemic stroke associated pneumonia after ischemic stroke and the predictive value of serum DAO and D-lac levels for SAP. Methods 80 patients with the first acute ischemic stroke from June 2018 to October 2018 and hospitalized in the Xuzhou Medical University affiliated hospital were selected as research ob＜x＞jects. According to the occurrence of SAP within 48h to 7d after the onset of ischemic stroke, the patients were divided into SAP group ( n=37) and non-SAP group (n=43). Peripheral venous blood was collected at the first, second and seventh days after the onset, and the activities of serum diamine oxidase (DAO) and d-lactate (D-Lac) concentration were determined. The data of basic clinical characteristics, DAO and D-Lac levels were compared between the two groups. Evaluate the predictive value of DAO and D-Lac to SAP. Results There were significant differences in age, history of diabetes, stroke area, disturbance of consciousness, dysphagia, mechanical ventilation, nasogastric nutrition, GCS score and NIHSS score between the SAP group and the non-SAP group (P < 0.05).The DAO level in the SAP group was higher than that in the non-SAP group at the first and second days after ischemic stroke, while the D-Lac level was higher than that in the non-SAP group at the three time points after ischemic stroke, and the difference was statistically significant ( P < 0.05). After stroke, DAO activity decreased with time and D-Lac concentration increased with time, and the difference was statistically significant (P < 0.001).The ROC curve showed that the AUC under the DAO curve at the first and second days after stroke was 0.711 and 0.687, the specificity was 82.9% and 86.9%, and the sensitivity was 61.9% and 42.9%.The AUC of D-Lac was 0.845 and 0.736, the specificity was 82.9% and 72.2%, and the sensitivity was 83.3% and 66.7%. Conclusions The occurrence of SAP in patients with ischemic stroke is related to the damage of intestinal mucosal barrier. Serum DAO and D-Lac levels were of predictive value for ischemic stroke associated pneumonia, and D-Lac was the most effective the first day after stroke onset.