Pulmonary actinomycosis is a chronic pulmonary infection characterized by suppuration, abscess formation, and dense scarring. The causative agent, Actinomyces israelii, is a gram-positive, microaerophilic bacterium that resemble fungi. We recently treated two cases of pulmonary actinomycosis. A patient was underwent right lower lobectomy under the impression of bronchiectasis. Pulmonary actinomycosis was diagnosed of postoperatively. He was medicated with high-dose penicillin parenterally. The other patient was also undergone right lower lobectomy under the impression of broncholithiasis and received parenteral penicillin and oral roxythromycin. There was no recurrence or development of empyema. The purpose of this paper is to review of our experience and to enhance consideration of pulmonary actinomycosis.