Background: The nails of hands and feet are involved in the course of many dermatoses and some systemic diseases. They may have diagnostic or prognostic value in some diseases. Objective: The aim of this study was to evaluate nail lesions in patients referred to Dermatology Department of Sina Hospital in Hamadan from April 1999 to April 2000. Patients and Methods: This cross-sectional descriptive study was done by preparation of a checklist and necessary information was collected by examining all the patients and recording the nail changes. The data were analyzed with EP16 software. Results: Among 2269 patients visited during this year, 630 persons (27.7%) had nail lesions. Eczema and psoriasis were the most common dermatosis with nail lesions (23.5% and 12%, respectively). Fifty-five patients (8.7%) had only nail diseases. Ridging was the most common nail lesion in hands (32%) and in feet (42%). Conclusion: Approximately one third of patients referred to the dermatologic clinic of Sina Hospital in Hamadan had nail lesions.