The invention discloses a dust removal device of a printing machine, which comprises a machine body, dust removal rollers are arranged in the body, film coils are driven between the dust removal rollers, a drawing hole is provided in the machine body, and an installation base is slidably connected to the drawing hole , There is a dust collection paper roll on the installation base, a card slot is fixedly connected to the installation base, an elastic pressure plate is provided on the inner wall of the card slot, and a limit block is provided on the dust collection paper roll, and the limit block is limited to the elastic pressure plate. In between, the body is provided with a fixed shaft, the fixed shaft is provided with a rotating rod, a brush roller is arranged between the rotating rods, and a fastener is provided on the fixed shaft, and the fastener is fixedly connected to the brush roller on the body. The invention is simple and convenient to install the dust collecting paper roll, can quickly and efficiently remove the dust on the film coil, and improve the cleanliness of the product surface; at the same time, adjust the angle of the brush roller, change the contact and pressure between the brush roller and the film coil, and improve Dust removal effect, to avoid damage to the film coil.