Background: There is an increase in the incidence rates of skin cancer in Chile. Aim: To study the clinical diagnostic accuracy (CDA) for skin cancer. Material y methods: CDA was defined as the percentage of agreement between clinical and pathological diagnosis. Approximately 600,000 pathological reports from five hospitals in Santiago were reviewed. A total of 2,593 skin tumours; 230 Malignant Melanoma (MM); 412 Squamous Cell Carcinoma (SCC) and 1,951 Basal Cell Carcinoma (BCC) were studied. These tumours were clinically diagnosed and surgically treated by dermatologists. The CDA was studied for each tumour, by the anatomical localization of the tumour, Breslow Index in MM, by age and sex of the patient. Results: The highest CDA was observed for BCC (76.2%); followed by MM (64.3%) and SCC (34.7%). By anatomical localization, for MM the highest CDA was observed in the soles (p <0.05); for BCC, the hightest CDA was in the face (p <0.05). No significant differences were observed in SCC. By age, for MM, the CDA was higher in patients aged less than 50 years. No differences in CDA by age were observed in the other two tumours. By sex, no differences were found. A higher CDA was found in MM with Breslow indexes III and IV than for MM with Breslow indexes I and II. Conclusions: CDA is affected by the clinical variables analyzed in this study. A more accurate clinical diagnosis of skin cancer could be obtained taking into account these variables (Rev Méd Chile 2003; 131: 1421-7).