Epidermodysplasia-verruciformis-associated human papillomavirus DNA has been demonstrated in squamous cell carcinomas and plucked hair from immunocompetent patients and renal transplant recipients. This study investigated the association between infection with epidermodysplasia-verruciformis-associated human papillomavirus, identified by the detection of viral DNA in plucked eyebrow hairs, and solar keratoses. These lesions are strongly predictive of squamous cell carcinoma. In a cross-sectional study 518 individuals were enrolled from a randomly selected sample of a subtropical Australian community. Epidermodysplasia-verruciformis-associated human papillomavirus DNA in eyebrow hair was detected using a nested polymerase chain reaction specific for epidermodysplasia-verruciformis-associated human papillomavirus types. Epidermo dysplasia-verruciformis-associated human papillomavirus DNA was present in 121 (49%) of 245 men and 116 (44%) of 262 women. There was a strongly significant increase in epidermodysplasia-verruciformis-associated human papillomavirus infection with age (p < 0.00001), with prevalences of 29% in the 25-39 y age group, 42% at 40-59 y and 65% in the 60-79 y age group. Among men there was a strong association between epidermodysplasia-verruciformis-associated human papillomavirus and solar keratoses with an odds ratio, adjusted for age, skin color, and occupational sun exposure, of 3.40 (95% confidence interval, 1.77-6.53). No such association was found among women [odds ratio 1.03 (95% confidence interval 0.59-1.77, after adjustment for the same factors)]. Differences in occupational sun exposure and smoking histories could not explain these apparently different associations between epidermodysplasia-verruciformis-associated human papillomavirus infection and solar keratoses in men and women. In conclusion, epidermodysplasia-verruciformis-associated human papillomavirus infection is associated with solar keratoses in men suggesting that epidermodysplasia-verruciformis-associated human papillomavirus infection, in conjunction with sex specific factors (like androgens), may be involved in neoplastic changes of keratinocytes.