The invention discloses a dustproof device for doors and windows. The dustproof device structurally includes a first left window, a second left window, a left hand shank, a right hand shank, a third right window, a dustproof apparatus, a second right window, a first right window, a right fixing decoration line, a right dustproof door, a left dustproof door and a left fixing decoration line. The first left window is fixedly connected to the second left window, A is movably connected with B, the right dustproof door is movably connected to the third right window, the second left window is movably connected to the left dustproof door, the third right window is movably connected to the second right window, the second right window is fixedly connected to the first right window, the left fixingdecoration line is arranged in the left dustproof door, and the right fixing decoration line is arranged on the right dustproof door. Through arrangement of a double-layer glass panel, the hardness and the dustproof effect are great.