We report an unusual case of Acinetobacter baumannii (A. baumannii) bacteremia in a man without significant comorbidities. A 50-year-old man who noticed a sudden onset of high fever was admitted to Kobe Nishi City Hospital. After the admission, his condition deteriorated rapidly with development of shock, anuria and agitation. Antibiotic therapy with meropenem and amikacin was begun for suspected septic shock along with the mechanical ventilation and continuous hemodialysis. Venous blood cultures yielded A. baumannii. No definite source of bacteremia was detected. Intensive medical management was effective, and he was discharged on the 27^th day. While the most common source of infection that leads to A. baumannii bacteremia is in the respiratory tract, community-acquired bacteremia with unknown foci is considered rare.