Objectives: To evaluate the risk factors for the development of occupational allergy to birds among Polish zoo garden keepers. Methods: A total of 200 bird zookeepers employed in the Polish zoo gardens in Łódź, Warsaw, Gdańsk, Chorzów and Płock and exposed occupationally to bird allergens were examined using a questionnaire, skin prick tests (SPTs) to common allergens and bird allergens, spirometry and cytograms of nasal swab. The level of total IgE in serum and serum-specific IgE to parrot, canary, pigeon feathers and serum were also evaluated. Results: Eight percent of bird zookeepers were sensitized to at least one of the bird allergens. The most frequent allergens yielding positive SPT results were D. farinae — 32 cases (16%), D. pteronyssinus — 30 cases (15%) and grass pollens (16.5%). In the studied group, allergen-specific IgE against bird allergens occurred with the following frequency: 87 (43.5%) against canary feathers and/or serum, 80 (40%) against parrot feathers and/or serum and 82 (41%) against pigeon feathers and/or serum. Occupational allergy was diagnosed in 39 (26.5%) cases, occupational rhinitis was present in 22 (15%) cases, occupational asthma in 20 (13.6%) subjects, occupational conjunctivitis in 18 (12.2%) cases, whereas occupational skin diseases in 11 (7.5%) cases. More eosinophils were found in nose swab cytograms among bird zookeepers with occupational airway allergy. Conclusions: The findings indicate that occupational allergy to birds is an important health problem among zoo bird keepers in Poland.