The invention discloses a simple solar water heater, which comprises a reflector, a heat collecting tube and a header. A reflector is installed under a horizontally arranged heat collecting tube. The side end is installed together with the heat collecting tube bracket arranged on the reflector, the bottom of the header is provided with the outlet pipe 2, the top of the header is provided with the water tank, the upper part of the water tank is provided with the water inlet pipe, and the lower part of the water tank is provided with the outlet pipe 1 , the header is also provided with a temperature sensor, the temperature sensor is connected to a controller, the outlet pipe is provided with a regulating valve, and the regulating valve is connected to the controller. The present invention has the advantages of reasonable design and simple structure. , Easy to process, small size, easy to use, low production cost, low failure rate, safe and reliable operation, etc., the water quality is good, non-toxic and tasteless, and the temperature sensor is used to control the temperature of the water in the box to ensure the temperature without causing energy waste. The water that has reached the water temperature is discharged to other places that need hot water through the controller, and at the same time, the problem that the scale cannot be discharged is solved.