To provide a vacuum cleaner which separates dust by physical force such as inertia force, centrifugal force, and the gravity.

A main stream is rotated along the guide plate of a curved surface projecting with respect to the flow of the main stream. By expanding the basin width of the flow of the main stream and making the thickness in the working direction of the centrifugal force thin, dust is put out to the outside of the flow of the main stream by a short moving distance and in a short period. By making the rotation surface of the main stream face vertically downward to be coincident with the direction of the gravity, a synergistic effect of the gravity and the centrifugal force is acquired. Between the flow of the main stream going out from the exit of a dust separation part after dust removal and a separation area, a pull-in prevention plate is provided to separate the separation area.