Desquamative interstitial pneumonia is a rare disease that is predominantly associated with smoking. Surgical biopsy is usually recommended for the diagnosis of this disorder. Probe-based confocal laser endomicroscopy (pCLE) is a new method of minimally invasive in vivo microscopic image of airways and alveoli. We use this method for desquamative interstitial pneumonia in nonsmoker. The pCLE image shows thickened intra-alveolar septae and clusters of autofluorescent cells within the alveoli, which is unusual for non-smoking patients. We think this pattern can be used for differential diagnosis of desquamative interstitial pneumonia in nonsmokers.