A 78-year-old man was referred to our hospital complaining of chronic productive cough. Physical examination revealed yellowish, thin nails and pretibial edema. A chest computed tomograph showed bilateral bronchiectasis. A sinus radiograph showed the findings of chronic sinusitis. From these findings, yellow nail syndrome was diagnosed. Long-term low-dose macrolide therapy with 400 mg/day clarithromycin was started and his symptoms began to gradually improve. However, complete resolution of his symptoms was not achieved and fiberoptic bronchoscopy was performed. Transbronchial biopsy specimen obtained from the right second carina showed bronchial asthma-like findings such as eosinophilic infiltration, thickening of the basement membrane, mucosal edema and goblet cell hyperplasia. Airflow reversibility was not detected. Thus a diagnosis of coexistence of yellow nail syndrome and eosinohilic bronchial disease was established. Further improvement of his symptoms was achieved by additional therapy with 800 microg/day budesonide and 100 microg/day salmeterol. To the best of our knowledge, this is the first report of a case of yellow nail syndrome associated with eosinophilic bronchial disease successfully treated with long-term low-dose macrolides and inhaled corticosteroids.