The invention discloses a solar water heater with an auxiliary heater. The solar water heater with the auxiliary heater comprises a water storage tank, the auxiliary heater, an installation frame, a heat collecting tube, a sealed connection piece, a water inlet pipe, a water outlet pipe, a rainwater collecting tank, a water collecting groove, a water return pipe, a filter screen, a heat collectingtube cleaning assembly and a reflector plate angle adjusting assembly, wherein the auxiliary heater is arranged in the water storage tank; the water storage tank is connected with the installation frame; the installation frame is provided with a front support frame and a back support frame; the front support frame is connected under the heat collecting tube; the upper end of the heat collecting tube communicates with the water storage tank through the sealed connection piece; the heat collecting tube is connected with the heat collecting tube cleaning assembly; and the back support frame is connected with the reflector plate angle adjusting assembly. According to the solar water heater with the auxiliary heater provided by the invention, the double-layer heat collecting tube is arranged,and a heat conducting fin is matched for transferring heat, so that cold water in the heat collecting tube is heated uniformly; by utilizing the belt drive and the pulling of a pulling rope I, the surface of the heat collecting tube is cleaned, so that a heat collecting performance is ensured; and a bevel gear I meshes with a bevel gear II so as to wind and unwind a pulling rope II, and the angleof a reflector plate is adjusted, so that sunshine is reflected to the back surface of the heat collecting tube, and a heat collecting performance of the heat collecting tube is improved.