ObjectiveTo improve the knowledge of pulmonary actinomycosis.MethodsThree cases of pulmonary actinomycosis in this hospital and 65 cases reported in China were analyzed retrospectively.ResultsAmong the 68 patients 49 were male and 19 were female aged 6 to 77 years old. The most common clinical manifestations were cough, sputum and fever. Inflammatory indicators was slightly elevated. The most common site was on the right upper lung. The typical CT manifestations were the low-density liquefaction necrotic zone in the center of the mass with vacuoles of different sizes, namely, "air-space consolidation". Positron emission computed tomography showed a mild metabolic increase in lesions. The 68 patients were confirmed by surgery, CT guided percutaneous lung puncture or bronchoscopic biopsy. The average time of the diagnosis was 10 months while the longest time was 6.4 years. The rate of first diagnosis was 5.9%. Forty-one cases were treated with antibiotics alone and 12 cases were treated with simple operation, the rest were treated by antibiotics combined with surgical treatment. The cure rate was 88.7%. Although active treatment was conducted 3 patients in this hospital were not cured.ConclusionsThe clinical features of pulmonary actinomycosis are atypical and the misdiagnosis rate is high. When pulmonary actinomycosis is suspected, it should be fully communicated with the microbiologist to ensure the cultivation in anaerobic environment and extension of the incubation cycle. Tissue culture and pathological biopsy should be actively performed. Treatment depends on antibiotics or surgery with good prognosis, but for some cases the prognosis is not optimistic.