Accurate clinical diagnosis of malignant melanoma is of great importance for early detection and further treatment. The purpose of this retrospective study was to evaluate the accuracy of clinical diagnosis by using different clinical and histopathological parameters. Calculations are based on a total of 44,258 histopathologically examined skin neoplasms, including 529 melanomas, which were recorded in the histological database of the Department of Dermatology, University of Graz during a 2 year period. The clinical diagnosis of the referring physicians was compared statistically with the final histopathological interpretation. Clinical diagnosis of melanoma showed a sensitivity of 70.1%, a specificity of 99.4%, and a positive predictive value of 60.7%. One hundred and fifty eight melanomas (29.9%) could not be diagnosed clinically. The age-dependent sensitivity was 47.6% in patients <40 years, whereas for patients >80 years the value was 90.2%. Remarkably, the sensitivity in melanomas >4 mm thickness (64.8%) was lower than in 'melanoma in situ' (72.6%). Our findings underline the importance of further development of clinical examination techniques such as dermoscopy and digital epiluminescence microscopy.