The authors carried out research into anti-Malassezia precipitating antibodies in the population, specifying the distribution by age and sex. A total of 868 serum specimens from subjects of both sexes, aged between 0 and 80 years, were studied. An immunoelectroprecipitation reaction was used using a M. furfur culture filtrate as antigen. No antibodies were found in children under 11 years, whereas they were present after that age and reached maximum frequency in subjects between 31 and 40 years of age. In subjects up to 50 years of age they were more frequent in women, but in subjects over the age of 50 years they were more frequent in men. Globally, antibodies were found in 31% (270/868) of the subjects examined. The presence of antibodies correlates with data from the literature regarding the isolation of this yeast in relation to age.