Herein, we reported on a case of solid type of pulmonary actinomycosis in a 10-year-old boy. He had productive cough for 40 days. Bronchoscopy was normal. Cmputed tomography revealed a solid large mass in the upper lobe of his left lung with mimicking malignant leisions. He was referred for surgery and underwent left upper lobectomy. Macroscopically, the specimen measured 13×9×5 cm and was creamy to whitish on cut section. Microscopic findings included a large number of inflammatory cells and colonies of actinomyces. Pulmonary actinomycosis should be included in the differential diagnoses of pulmonary mass lesions, especially in the young adults.