Objective: Pigmented purpuric dermatosis (PPD) is a chronic skin disease characterized by petechial and pigmentary macules. The etiology of the disease remains unknown. Mean platelet volume (MPV) is a marker of platelet (PLT) function and activation. PLTs play important roles in inflammation and innate and adaptive immunity in addition to their roles in hemostasis and thrombosis. In this study, we investigated the possible association between MPV and PPD.Methods: Forty patients with PPD were enrolled in the study. The control group consisted of 64 healthy subjects. The study design was retrospective. The age, gender, and MPV and PLT levels were recorded from patients' charts. Cases who had received any medicine affecting PLT function and had a concomitant disease were excluded from the study.Results: The mean MPV levels were 9.7±2.1 fl and 8.0±1.1 fl in the patient and control groups, respectively. This difference was significant (p<0.001). The mean PLT levels were 246.2±55.8 and 261.6±49.6 in the patient and control groups, respectively. There was no significant difference in the PLT counts between the two groups (p=0.169).Conclusion: In this study, we found a significant correlation between MPV and pigmented purpuric dermatosis. There is a need for more detailed and prospective studies to determine the possible role of increased PLT activation in the pathogenesis of the disease.