The invention discloses a
polishing device for surfaces of building boards. The
polishing device comprises a support, a
polishing device body, a wire, sliding rods, a fulcrum bar, a control cabinet, a collection box, a fixing groove, a base, suction holes, clamping plates, a bearing frame, extending and retracting rods, a limiting clamping plate, a polishing disk,
lantern rings, a rotating rod, an inner rod and a spring. The polishing device has the beneficial effects that the two sliding rods are arranged in the support, the polishing device body is arranged on the sliding rods through the
lantern rings, the polishing device body can slide on the sliding rods to adjust the polishing position in the polishing process, and therefore uniform polishing is achieved. The suction holes are formed in the inner wall of one side of the fixing groove and communicate with a draught
fan in the collection box, chippings produced in the polishing process can be absorbed into the collection box through the suction holes, and the situation that the chippings produced in the polishing process affect the polishing effect is avoided. By arranging the clamping plates which can extend and retract are arranged on the inner walls of the two sides of the fixing groove, the building boards are fixed through the extending and retracting clamping plates, and therefore it is ensured that the boards cannot shake in polishing.