The invention discloses a preparation device for water-changing water-stop strips, which comprises a bottom plate, a support is provided on the bottom plate, an unwinding wheel is provided on the support, a dipping tank is provided on the inner bottom of the support, and a dipping wheel is provided on the inner bottom of the dipping pool , the bracket is provided with a traction wheel, the bracket is equipped with a wiper tube, the bracket is equipped with an electric heating tube, an electric heating plate and a temperature controller, the electric heating plate is installed on the upper part of the electric heating tube, and the electric heating plate and the temperature controller are electrically connected; the bracket The second guide wheel is arranged on the top, the driving wheel is arranged on the bracket, the driving wheel is engaged with the second guide wheel, the driving motor is arranged on the bracket, the front part of the driving motor is provided with a driving shaft, and one end of the driving shaft is connected with the driving motor. The driving wheel is set on the other end of the driving shaft; the unwinding wheel, the traction wheel, the dipping wheel, the ink scraping tube, the electric heating tube and the second guide wheel are connected in sequence. The invention can heat-treat the water-stop strip through the electric heating tube, and can form a water-changing color layer on the surface of the water-stop strip; and can conveniently guide and recycle the water-stop strip.