Bronchiolitis obliterans is a clinical syndrome of chronic obstruction associated with inflammatory changes in the small airways. There are marked variations in the epidemiology of this disease. In childhood, bronchiolitis obliterans has been described as a result of a number of infections such as adenovirus, measles, Bordetella pertussis, Mycoplasma pneumoniae, and influenza A infection. Most common agents are adenovirus types 3, 7, and 21. Diagnosis of bronchiolitis obliterans can be made based on clinical findings, high resolution computed tomography (HRCT) and lung biopsy. In addition to diagnosis, treatment is not yet clearly established. The authors experienced a case of bronchiolitis obliterans developed in 3 year-old girl who suffered from type 7 adenoviral pneumonia. She had been hospitalized and treated for 15 days due to pneumonia. After discharge, productive cough was not improved and auscultation revealed wheezing. HRCT demonstrated multifocal mosaic patterns suggesting bronchiolitis obliterans. She was managed with inhaled steroid and bronchodilator, and her symptoms were improved. However, follow up HRCT showed no interval change.