We report the case of a patient working in a factory producing inulin from chicory who developed rhinoconjunctivitis and asthma to the dust of dry chicory roots and oral allergy syndrome to raw fruits and vegetables. Nonspecific bronchial hyperresponsiveness was diagnosed. A provocation test with dry chicory induced acute rhinoconjunctivitis and an immediate asthmatic response with no further clinical symptoms. Skin prick test results were positive to birch pollen and fresh/dry chicory, and negative for inulin. Specific immunoglobulin (Ig) E was > 100 kU(A)/L for rBet v 1. Specific IgE were detected by immunoblotting chicory extract with the patient's serum, but not with a control serum. The main immunoreactive band corresponded to a protein with a molecular weight of approximately 17 kDa, like Bet v 1, and this immunoreactivity was effectively inhibited by preincubating serum with purified Bet v 1. This case documents occupational rhinoconjunctivitis and asthma due to IgE sensitization to inhaled chicory allergens, including one identified for the first time as a 17-kD Bet v 1 homologous protein, with secondary oral allergy syndrome to related foods.