AIM OF THE STUDY: To evaluate the differences about incidence, kind and clinical features of thyroid diseases in young and elderly patients. MATERIALS AND METHODS: Our study has been conducted in Endocrine Surgery Unit, “S. Luigi and S. Currò” Hospital in Catania, from January 2001 to December 2003. In this period 621 patients affected with different thyroidopathies were observed. They were divided in two groups: elderly (65 years or older), named Group A, and young subjects (under 65 years old), named Group B. Group A included 147 people aged between 65 and 89, with F:M=3.9:1. Our study was founded on clinical and laboratory evaluation of thyroid hormones and antibodies (AAT, AMT) and subsequently an ultrasonographical evaluation, that has been completed, in some cases, with cytologic examination (FNAc). CONCLUSION: The main aspect about thyroid diseases is the different and atipycal presentation in the elderly in comparison to young patients, with subsequent difficult diagnosis due to common symptoms to thyroidopathies rather than to physiological ageing. The most common thyroid dysfunctions in elderly are the autoimmune thyropaties, responsible of hypothyroidism. Such condition, in elderly, is often clinically irrelevant.