Pulmonary emphysema is very uncommon in children in the first decade of life. The few cases documented in the literature were all due to α1-antitrypsin deficiency. We present the case of a 6-year-old white boy with chronic cough and dyspnea on exertion. Lung biopsy showed panacinar type emphysema with patent airways and diffuse hyperplasia of pulmonary neuroendocrine cells revealed after immunostaining for bombesin, a peptide produced by these cells. We speculate that idiopathic diffuse hyperplasia of bombesin-producing pulmonary neuroendocrine cells may contribute to the pathogenesis of unusual COPD in childhood.