The invention discloses a high-efficiency dedusting device. The device includes a base, the left side of the top of the base is fixedly provided with a supporting rod, the right side face of the top of the base is internally provided with a guide chute, the guide chute is internally provided with a guide sliding rod in a left-and-right extending mode, the guide sliding rod in the guide chute is connected with a slide supporting rod in a sliding and matched mode, the slide supporting rod extends upward, the sides, opposite to each other, of the supporting rod and the slide support rod are provided with a first dedusting part and a second dedusting part respectively, a first empty cavity is formed in the supporting rod, the first empty is internally provided with a first rotating rod in a left-and-right extending mode, a first cone pulley is fixedly arranged on the first rotating rod, the bottom of the right side of the first cone pulley is connected with a second cone pulley in a meshedmode, a rotating sleeve is fixedly arranged on the second cone pulley and extending toward the right side, the extending part of the right side of the rotating sleeve penetrates through the right side face of the supporting rod and is connected with the right side face of the supporting rod in a rotating and matched mode, and the tail end of the rotating sleeve is fixedly connected with the firstdedusting part. The device is simple in structure, the length adjusting speed and the dedusting stability are improved, adjusting steps are simple, and the whole working process is accelerated.