One of the known complications of diabetes is hearing impairment. This comparative study in Tehran, Islamic Republic of Iran, aimed to evaluate the association of diabetes mellitus and sensorineural hearing loss (SNHL) among a non-elderly population. Among 160 subjects aged < 60 years with no history of occupational noise exposure (80 diabetics and 80 age- and sex-matched non-diabetic controls), 45% of diabetic patients and 20% of controls had SNHL (OR 3.5, 95% CI 1.6–6.6). Age at onset and duration of diabetes were associated with SNHL. Diabetes mellitus may be a risk factor for hearing loss regardless of age and smoking. Determining the cause of SNHL in diabetic patients may lead to development of better treatment options.