Objective: Assessment of the systemic inflammatory response of the neutrophil lymphocyte ratio (NLR) and platelet lymphocyte ratio (PLR) is shown as a new biomarker. Red cell distribution width (RDW) is the size of red blood cells and have been found related to adverse events in many diseases. Mean platelet volume (MPV) indicates platelet volume and platelet volume is a potential indication of platelet activity. The aim of our study is to investigate hematological changes in patients with panic disorder (PD) through readily available markers such as NLR, PLR, RDW and MPV. Methods: Thirty-nine patients between the ages of 18 and 75 who were diagnosed with PD according to DSM-5 (Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition) and forty healthy control subjects were included in the study. MPV, NLR, PLR and RDW were measured and recorded for groups. Hamilton Depression Scale, Hamilton Anxiety Scale, Clinical Global Impressions Scale (CGI-S) and Panic Disorder Severity Scale were applied to the patients. Results: There were no statistically significant differences between groups in terms of sociodemographic characteristics. No significant correlation was found between NLR, PLR and RDW values and clinical scales. MPV was negatively correlated with the severity of panic disorder. There was no correlation between MPV and other variables. Conclusion: Our study is the first study to examine NLR, PLR and RDW associations in PD patients. There are studies showing that increased sympathetic activity leads to increased MPV. In our study, the MPV value did not differ between PD and control group. However, there was a negative correlation between the severity of panic disorder and MPV.