OBJECTIVE The purpose of this study was to identify characteristic radiographic findings in children with pulmonary blastomycosis. METHODS We reviewed the charts and radiographs of 18 children with culture-proven acute pulmonary blastomycosis. The 10 boys and eight girls were from 1 to 16 years old. Sixteen were Native Canadian Indians, and two were white. All available chest radiographs, including those obtained in follow-up after treatment was terminated, were reviewed by a pediatric radiologist. Consolidation was classified by location and extent, and other abnormalities were noted. RESULTS Initial chest radiographs showed consolidation in 16 patients. Seven patients had single lobe involvement, most commonly of the left lower lobe. Nine patients had multiple lobe involvement. The left lower lobe was most commonly involved in these cases, but the middle lobe was most severely affected. The upper lobes were involved only in children with multiple lobe disease and were only mildly affected. Cavitation developed in two patients, followed by bronchogenic spread of the disease. Pleural effusions were seen in three patients; two also had rib lesions. Hilar adenopathy developed in two children. Five patients had radiographs available, which had been obtained more than a year after onset, and three of these were abnormal. CONCLUSIONS The most common radiologic finding in children with pulmonary blastomycosis is pulmonary consolidation in one or several lobes, which may undergo cavitation. Lymphadenopathy and pleural effusions are uncommon. Chronic abnormalities may develop.