Various aetiopathological mechanisms have been postulated to be at the root of Menière's disease (MD), and some data suggest that there may be also an underlying autoimmune factor. In fact, Menière patients manifest certain characteristics that are typical of autoimmune involvement association of particular human leucocyte antigen haplotypes, the presence of antibodies against internal ear antigens. In this study, we evaluated the association between thyroid autoimmunity and MD in a non-selected group of patients. We recruited 50 consecutive MD patients and two groups as controls: group A, 82 healthy volunteers; and group B, 50 subjects suffering from acute unilateral peripheral vestibulopathy. All subjects were submitted to instrumental assessment of cochlear-vestibular function and analysis of thyroid-stimulating hormone (TSH), free triiodothyronine, free thyroxine, anti-TSH receptor antibody (TR-Ab), anti-thyroperoxidase antibody (TPO-Ab) and anti-thyroglobulin antibody (Tg-Ab) in the blood. The prevalence of autoimmune thyroiditis in group B [6/50 (12%); 66.7% TPO-Ab and 33.3% Tg-Ab] was superimposable with the healthy controls [6/82 (7%); 66.7% TPO-Ab and 33.3% Tg-Ab]. In contrast, 38% of the MD patients (P = 0.0001 versus group A and group B) had significant autoantibody levels (68.4% TPO-Ab; 15.8% TPO-Ab + TR-Ab; 10.5% Tg-Ab; 5.2% TPO-Ab + Tg-Ab). Furthermore, 14% of the MD patients were hyperthyroid under l-thyroxine therapy, while no dysfunction was seen in the control groups. Overall, our data demonstrate a significant association between MD and thyroid autoimmunity, which suggests that an autoimmune factor is involved in the aetiopathogenesis of this disease. These findings suggest that it should be useful to submit MD patients to multi-disciplinary clinical investigation.