The invention discloses a dust collector. The dust collector comprises a dust collection container, an incoming air inlet, a closed valve for closing the incoming air inlet when being located in a closed position, a tray and a filter installed on the tray, wherein a suction opening is formed in the tray; and air after being filtered through the filter flows through the suction opening. The dust collector also comprises a motor for providing a suction power; the motor is positioned on the upper side of the tray and the filter is positioned on the lower side of the tray; at least one ventilationopening at an interval with the suction opening is further formed in the tray; the ventilation opening is used for enabling a fluid to be connected between the inner cavity of the filter and the incoming air inlet; when the filter is cleaned, air can enter into the filter through the incoming air inlet and the ventilation opening after the filter is opened and the air is applied to the surface, back to the dust collection container, of the filter. Through the design, the ventilation opening is additionally formed in the tray, air introduced from the incoming air inlet can be supplied for theinner cavity of the filter through the tray, the filter is cleaned, and the function of the tray is added through the design, so that the practicability of the tray is strengthened.