A 73-year-old woman complaining of cough and dyspnea was admitted to our hospital. High-resolution computed tomography chest revealed patchy ground-glass attenuation in the upper lung field. The patient suffered an asthma attack and was diagnosed with allergic pneumonitis; prednisolone was administered for treatment. Bird-related hypersensitivity pneumonitis was suspected, as she had a gray parrot (Psittacus erithacus) and a budgerigar (Melopsittacus undulatus) at home. An immunoblotting analysis with the patient's serum demonstrated IgG-binding fractions to the gray parrot's feathers only; no binding was noted with the budgerigar antigens. The patient was conclusively diagnosed with hypersensitivity pneumonitis related to exposure to a gray parrot.