Between 1998–2000 epidemiological research was carried out in various centres, with an aim of estimating the frequency of allergy-based diseases in Poland. The objective of this work was an attempt to evaluate the occurrence frequency of aspirin-induced asthma in the population of adults in Poland based on the epidemiological questionnaire. Clinical verification was carried out in detail for all patients with suspected aspirin-induced asthma. Analyses concerned 75 persons with symptoms of hypersensitivity to NSAIDs. Control group of 72 asthmatics with good tolerance to aspirin from the Kraków was identified. Bronchial asthma was diagnosed in 582 persons (5.4 %). Of that group, 75 patients (12.9 %) additionally complained of symptoms of hypersensitivity to NSAIDs. Aspirin-induced asthma was diagnosed in 11 patients (14.7%) of the group of persons with clinical manifestations of hypersensitivity responses. Frequency of aspirin-induced asthma with clinical symptoms amounted to 1.9% of asthmatics. Frequency of aspirin-induced asthma in the whole examined population of adults in Poland amounted to 0.1%. In statistical analysis in the assessment of severity of the disease, applying logistic regression model - aspirin intolerance was the only statistically significant factor to impact severity of the disease (p=0.0003; odds ratio 28.6 with assumed 95% confidence interval). Chronic sinusitis occurs in nearly half of the bronchial asthma patients with hypersensitivity to NSAIDs and clinical manifestation of atopy occurred in a similar ratio as in the population of asthma patients with no traits of hypersensitivity.