We evaluated and compared blood total platelet count, mean platelet volume (MPV) and platelet distribution width (PDW) values of patients with erectile dysfunction (ED) and control subjects. A total 57 male patients (mean age 49.7 +/- 12years) with ED and 59 control men (mean age 49.7 +/- 10.7years) were included in the study. All patients were evaluated using medical history with International Index of Erectile Function (IIEF) scores, physical examination and routine blood analysis. Total blood count, including white blood cell (WBC), total platelet counts, MPV and PDW parameters, were recorded in both groups. MPV values were detected to be significantly higher in patients with ED than control group: 10.7 +/- 1 and 9.72 +/- 1.5, respectively (P=0.001). Similarly, PDW values were significantly higher in patients with ED than control group: 14.6 +/- 2.8 and 12.9 +/- 1.9, respectively (P=0.001). However, mean platelet and mean WBC counts were similar in both groups (P=0.45). We demonstrated that MPV and PDW values significantly increased in patients with ED compared with the control group. According to these findings, platelet function might play an important role in patients with ED that warrants further research.