Mean platelet volume (MPV) is one of the platelet function indices which reflects the platelet production rate and functions. While vascular occlusion, acute or chronic syndromes and vasculitis are increasing the MPV levels, infections, autoimmune diseases, and inflammatory situations reduce it. The indicator for idiopathic sudden sensorineural hearing loss (ISHL) etiology remains a matter of debate because it is associated with many different disorders. We evaluated MPV levels in ISHL patients. Forty patients with ISHL and 40 healthy, age and sex matched subjects were enrolled to the study. Audiometer and laboratory results were recorded. Comparative multivariate analyses between indicator factors and hearing outcomes were conducted. MPV and platelet distribution width is significantly higher in ISHL. Platelet count is lower in the ISHL than control group (p < 0.001), (p < 0.001), (p = 0.003), respectively. Our findings indicate that, ISHL appears to be characterized by ischaemic or thrombotic events. Considering the increased MPV levels; MPV may be used to evaluate ISHL as an hepler indicator.