The objective of our study was to evaluate the impact of sex and age on the prevalence of sensitization to inhalant allergens. The study was performed as a part of Polish Epidemiology of Allergic Diseases study, and data concerning citizens of Wroclaw were analyzed. The participants were divided into three age groups (6–7, 13–14, and 20–44 years) with a subdivision according to sex. We randomly selected 1409 individuals, 439 people complied; the complete set of tests was performed on 421 of them. We found that 37.7 % of the study population demonstrated sensitization to at least one of the allergens tested. Positive skin tests were found more frequently in males than in females (p = 0.003); among 6–7-year-old children, the sensitization was independent of sex (p = 0.26), while in two other groups, it was higher in males (p = 0.002 and p = 0.03, respectively). Clinically asymptomatic sensitization (AS) was found more often in females than in males (p = 0.04). The higher rate of AS in women was observed only in the two younger age groups, while in the 20–44-year-old group AS did not differ between the sexes (p = 0.72). Female sex hormones may contribute to a later change in the nature of sensitization from clinically asymptomatic to symptomatic. Further studies are needed to confirm the results of our study.