The case of a 43 year-old healthy male with Pseudomonas aeruginosa pneumonia causing septic shock and multiorgan failure within 48 hours of admission is presented. The patient had systemic symptoms and in the chest x-ray, minimal infiltration on the left upper zone was observed. After 36 hours of admission pneumonic infiltration involved all the left lung and the patient was admitted to the intensive care unit for invasive mechanical ventilatory support. Despite appropriate antibiotherapy and supportive therapy, the patient developed pancytopenia, septic shock and multiorgan failure and died 48 hours after admission. Pseudomonas aeruginosa was isolated from the sputum, blood and tracheal aspirate cultures. This case is presented because Pseudomonas aeruginosa pneumonia with fulminant fatal progression in a healthy adult without immunedeficiency, concomitant disease or risk factor is very rarely seen in the literature. (Tur Toraks Der 2010; 11: 134-7)