Epidemiological studies have shown solar exposure to play an important role in the appearance of skin cancer. We investigated the association between mortality standardized by the indirect method for malignant skin melanoma and other skin cancers and the mean intensity of solar radiation during July and August for the different provinces in Spain. A statistically significant relation was observed (p less than .05) for these two months but not upon considering mean annual solar radiation. We thus suggest that intermittent, intense exposure to sunlight constitutes an important risk factor for skin cancer. We observed an 8.5% and 15.72% increase in mortality due to malignant skin melanoma and other skin cancers, respectively, during the period 1975-1983. Mortality was slightly higher among males than females.