Objective: To describe the ecology in pleural infections, where nosocomial and community-acquired infections may have different ecology. Methods: retrospective single center study. Any subject admitted in intensive care unit with a diagnosis of complicated pleural effusion (presence of macroscopic pus, or sero-fibrinous pleural effusion with pH <7.2 or LDH >1000 or pleural glucose <0, 4 g/L, and signs of infection or positive bacteriological sampling) were included. Results: From 2006 to 2012, 57 patients were included. Four strains of “Multi-resistant” bacteria were reported in 3 patients with community-acquired pleural infection. As a whole 3 out of 57 (5%) patients had microorganisms (not including candida and mycobacteria) resistant to co-amoxiclav. It was not different between nosocomial and community-acquired pleural infections. Conclusion: Our study found resistance to co-amoxiclav in 14% and “multi-drug resistance” in 8% of the patients with community-acquired pleural infection.