The invention discloses a dust-proof blackboard, comprising a blackboard body located in the wall, wherein an inner cavity is formed in the wall, the front end of the inner cavity is provided with bumps, the inner walls of the bumps define a blackboard insertion part, the rear end of the inner cavity is provided with blackboard moving cylinders, the blackboard body move forwards to extend into theblackboard insertion portion, the rear end faces of the bumps are provided with two baffles capable of moving up and down, when the two baffles move up and down and cling to each other, the blackboard insertion portion is completely covered, two blackboard erasers are arranged on the left and right sides of the inner cavity, each blackboard eraser comprises an eraser body fixing block and a flexible eraser body, an oblique erasing strip is arranged on the end surface of the side, facing the blackboard body, of each flexible eraser body, and when the oblique erasing strips move towards the middle of the blackboard body, the oblique erasing strips extrude a blackboard slope part to enable the blackboard slope part to be gradually deformed until the oblique erasing strips are attached to theblackboard body, and the oblique erasing strips, close to each other, of the two flexible eraser bodies are attached to each other when the two blackboard erasers move to the middle of the blackboardbody, and air suction holes are arranged at the bottom of the inner cavity. The dust-proof blackboard integrates the function of writing, erasing, air blowing and dust suction, and is convenient andreliable to use.