The aim of this study was to examine the prevalence of signs and symptoms of temporomandibular joint (TMJ) dysfunction in persons with Marfan syndrome. A questionnaire was distributed to 350 patients with Marfan syndrome. Twenty-one patients were additionally subjected to a clinical examination and magnetic resonance imaging (MRI) of the TMJ. The prevalence of symptoms of TMJ dysfunction was 51.6% (n=145), with 24.2 % (n=68) indicating symptoms of subluxation, and 34.9% (n=98) of the patients already undergoing medical treatment for their TMJ problems. Anterior disc displacement with and without reduction was observed in 17 of the examined patients (81.0%), with 4 of these patients additionally showing osteoarthrosis of the affected temporomandibular joints. TMJ dysfunction appears to be an important aspect in Marfan syndrome.