In a renal failure patient, asthma developed after 1 year hemodialytic treatment. The attack was exclusively associated with each hemodialysis. Skin test to the usual allergen such as house dusts or pollens was negative. The provocation test by inhaling acetate solution or oral intake of acetic acid was positive resulting in an increase in the pulmonary resistance, or asthmatic attack. This asthma disappeared completely after substitution of acetate in the hemodialysis by the use of a bicarbonate dialysate. Acetate might therefore precipitate the attack of asthma.