When the electrically driven fan (14) of a vacuum cleaner is driven, air containing dust is drawn into the cleaner main body (1) through a hose (7) connected to a hose socket (8) and is exhausted into the outside of the cleaner main body (1) through an exhaust port (1b) via first and second suction passageways (10, 13). Disposed outside the first suction passageway (10) is an ion generator (23), it being arranged that plus and minus ions generated in the ion generator (23) are fed to the air stream flowing in the first suction passageway (10). Since the plus and minus ions kill floating germs in the air stream, the exhaust can be purified.