Abstract: Objective To investigate the incidence and influencing factors of cognitive dysfunction in elderly patients with acute ischemic stroke(AIS). Methods From January 2013 to September 2016, 725 patients with AIS in the third people's Hospital of Haikou were selected and 426 patients were included in the analysis of cognitive dysfunction using mini mental state examination (MMSE). Accordingly, the total 426 cases were divided into cognitive dysfunction group with 201 cases and normal cognitive function group with 225 cases. The influencing factors of cognitive impairment in patients with acute ischemic stroke were analyzed by single factor and multiple Logistic regression analysis. Receiver operating characteristic(ROC)curve was used to evaluate the effect of the logistic regression model. Results Single factor and multivariate Logistic regression analysis showed that history of hypertension, hyperlipidemia, hyperhomocystinemia, physical exercise, exchange frequency and ability of daily life were independent influencing factors for stroke patients with cognitive dysfunction (all P<0.05). The area under the curve(AUC) was 0.853(95% CI:0.781-0.926) under the effect of the logistic regression model by the ROC curve. MMSE score of groups with more than three independent risk factors was significantly lower than that of groups with less than three independent risk factors (t=4.183,P=0.016). Conclusions The incidence of cognitive dysfunction in elderly patients with acute ischemic stroke is high. There are a large number of risk factors for cognitive dysfunction. Preventive measures should be taken to reduce or delay the occurrence of cognitive impairment.