Abstract: Although there is plenty of research on the etiology and treatment of tinnitus, a definitive conclusion has not been reached in most studies. Among etiological factors, vascular and hematological abnormalities can be defined as an important cause in the evaluation of tinnitus cases, and these factors may underly many structural and functional problems. In this study, we aimed to investigate whether there was a correlation between platelet mass index (PMI) and tinnitus. To our knowledge, this is the first study exploring the effect of platelet mass on tinnitus. After reviewing the detailed medical records of 1,079 tinnitus patients that presented to our clinic between January 2019 and May 2020, the hemogram values of 177 cases meeting the study criteria were evaluated. There was no statistically significant difference between the patient and control groups in terms of mean age, gender distribution, and RBC (Red Blood Cell) neutrophil, lymphocyte, PLR and NLR levels (p>0.05). Compared to the control group, the hemoglobin and MPV levels of the patient group were statistically significantly higher (p<0.001), and the platelet level was statistically significantly lower (p=0.033). In addition, the PMI level of the patient group was significantly higher than that of the control group (p<0.001). In conclusion, the NLR, PLR and MPV values were found to be higher in the tinnitus group compared to the control group, as expected. Furthermore, the additional data for tinnitus cases showed that PMI was also observed to be significantly higher compared to the control group, indicating that the study objective was reached. PMI seems to be a predictive value for tinnitus, even in patients with MPV values lower than the normal range. Therefore, we consider that PMI is more sensitive than other markers, especially MPV in inflammatory events.