The lymphocyte / monocyte ratio (LMR) obtained by dividing the number of lymphocytes by monocyte number is considered a new marker of inflammation. Recent studies have found an inverse relationship between LMR levels and 3-month functional recovery after acute ischemic stroke (AIS). Our aim in this study is to determine the role of LMR in the short-term mortality of AIS patients. Method: Our study is a single centered retrospective study. 508 patients with AIS, who presented to our clinic between January 2011 and December 2017 and 512 healthy control with similar age and sex were included to our study. Results: While monocyte count was higher in the patient group; lymphocyte count and LMR levels were higher in the control group. The patient group was then divided into two subgroups according to 30-day mortality. When the patients in the first group survivied (n = 396), the patients in the second group died within 30 days after AIS(n = 112). In the second group, the lymphocyte count and LMR levels were lower when the monocyte count was elevated (p < 0.001). Logistic regression analysis showed that uric acid, CRP and LMR are independent variables for the occurrence of 30-day mortality. In addition, ROC analysis revealed that an LMR value below 2.95 can be used as a marker for the short-term mortality of AIS (AUC:0.77, %95 CI:0.67-0.86,sensitivity:%72.6, specificity: %80.7). Conclusions: Based on our results, it can be concluded that lower LMO levels in patients with AIS are related to shortterm mortality.