Dustproof cut-to-size saw

The utility model provides a dustproof cut-to-size saw. The dustproof cut-to-size saw comprises a machine body, a saw blade, a machine table, a guide rail, a sliding table, a bracket, a supporting arm, a sliding rod, a sliding block and a positioning piece. An upper dust suction hood and a lower dust suction hood are arranged above and below the saw blade respectively, the upper portion of the sawblade extends into the upper dust suction hood, the lower portion of the saw blade extends into the lower dust suction hood, and the top of the upper dust suction hood and the bottom of the lower dust suction hood are each connected with a dust suction pipeline. The upper suction hood can swing back and forth around the front end of the top, the height of the lower edge of the upper suction hoodis gradually reduced from front to back, the front end of the lower edge is higher than the upper surface of the sliding table, the higher height is not smaller than the thickness of a to-be-machinedplate, and the rear end of