Bovine epithelial and urine antigen extratcts were compared using enzyme‐linked immunosorbent (ELISA) inhibition assay and sodium‐dodecyl‐sulfate‐polyaerylanmide gel electrophoresis (SDS‐PAGE.) with immunoblotting. Accroding to ELISA inhibition results, the two extracts share about 2% of their antigenic components. Urine‐derived antigens seem to be antigenically closer to serum proteins than epithelial antigens were directed mainly against a protein of 20 kD, while non‐ allergy farmers had only very weak reactions. Generally, the IgG responses of allergic farmers against epithelial antigens were directed mainly against a protein of 20 kD, while non allergic farmers had only very weak reactions. Generally, the IgG response against urinary antigens farmers reacted with a band at 20 kD in IgE immunoblotting against urinary and epithelial antigen while all non‐allergic farmers showed n