Objectives The purpose of this retrospective study was to compare the mean platelet volume between the patients with acute deep vein thrombosis (DVT) and control subjects. Methods Data were collected retrospectively from the patients' medical records. The study group consisted of 110 patients with newly diagnosed acute DVT in the lower extremities. An age, gender, and body mass index-matched control group consisted of 98 patients with normal duplex ultrasound findings. We compared the mean platelet volume in patients with acute DVT and control participants. Results There was no significant difference between the study and control groups in mean platelet volume (8.8±1.6 vs 8.7±1.3 fl, respectively; p>0.05). Age (p=0.899), body mass index (p=0.43), gender (p=0.466), and platelet count (p=0.886) were statistically similar in both groups. Conclusions There was no significant difference in mean platelet volume between patients with acute DVT and the control group. According to our result, we propose that mean platelet volume should not be considered as an index of acute DVT.