This gentleman is 60 years old working as a physician in Derha, Syria, who was admitted with cough and dyspnea without fever, and he was found to have a large left pleural effusion; during his stay in the ward, the patient was treated as follows: large pleural effusion in the left side, as it was suspected to be malignant especially because the patient has a history of smoking. In our department, there is a suspicion of malignancy but showed large pleural effusion. In the second day of admission, the patient developed fever about 39 °C. A diagnostic procedure was done; insertion of needle to the pleural space was done to obtain some fluids for the diagnosis; the analysis of the fluids showed an acidotic fluid with low pH that was compatible with the diagnosis of empyema of the lung as a complication of pneumonia; the patient then had a pleural drainage with large thoracic tube and large spectrum of antibiotic as piperacillin/tazobactam was started. His culture from the pleural effusion showed the presence of Actinomyces odontolyticus bacteria.