A total of 1,132 pleural fluid culture results obtained from October 2012 to July 2014 were analyzed to elucidate the microbiological characteristics according to transudative and exudative pleural fluid. The pleural fluid cultures were performed using aerobic and anaerobic blood culture bottles. The blood and pleural fluid for total protein, lactate dehydrogenase, and glucose measurement were submitted to laboratory at the same time with pleural fluid cultures. The rates for culture positivity, anaerobes isolation, and polymicrobials between transudative and exudative pleural fluid were 5.2% vs. 10.4%, 14.8% vs. 7.8%, and 14.8% vs. 10.9%. (Ann Clin Microbiol 2015;18:52-55)