Interstitial pneumonia is a heterogenous group of inflammatory and fibrosing lesions that manifest themselves as infiltrative lung disease. Of these, nonspecific interstitial pneumonia is characterized as a variable degree of interstitial inflammation with or without fibrosis and is distinguished from usual interstitial pneumonia and desquamative interstitial pneumonia, histologically. The influx of inflammatory cells and the responses of immune effector cells injury to the alveolar wall and these initial injuries results in alveolitis and fibrosis. Consequently, the gas exchange throughout the alveolar wall is impaired and the patients suffer from lung diseases of a restrictive pattern. The chief complaints represented are dyspnea and dry cough. We experienced a case of nonspecific interstitial pneumonia in a 10-year old girl. The patient had been healthy and had not been exposed to organic dusts or other toxic materials. The pathology of lung biopsy tissue showed that the alveoli were thickened by a mixture of chronic inflammatory cells and collagen type fibrosis. High resolution computed tomography(HRCT) found the patchy areas of ground-glass opacity with patchy consolidation and irregular reticular opacity, and diffuse distribution without zonal predominance. The forced vital capicity(FVC) was 31%, forced expiratory volume in one second (FEV1) 29% and FEV1/FVC 90%, so a restrictive pulmonary insufficiency was found.