Application of the panting method is very difficult for patients with pulmonary emphysema (PE). We attempted to measure airway resistance (Raw) during quiet breathing and changing respiratory rate step by step in patients with PE using a pressure-type body plethysmograph system (BX-82) correcting measured values by temperature and humidity. Influence of the respiratory rate to Raw was studied at 0.5l/sec of inspiratory and expiratory flow. Whenever the respiratory rate was going up, the Raw increased in spite of the increase of the thoracic gas volume. Raw (2Hz) was about one and a half times as high as Raw (quiet breathing). On the other hand, when the respiratory rate was going up, elevation of the peak flow was always able to be recognized. It seemed that the state of the airway varied during the panting method. The Raw measured during 0.5 Hz breathing (nearly quiet breathing) had small variability. Because the airway state during 0.5 Hz breathing was nearly the same as that during quiet breathing, measurement of Raw (0.5Hz) can be regarded as a practical method in patients with PE.