Although traditional solar water heaters bring great convenience to people’s life, there are still shortcomings such as slow start-up speed and poor thermal conductivity. Therefore, in order to improve the performance of solar water heaters, this paper designs a heat pipe solar water heater system based on heat pipe technology, and uses experiments to analyze the heat transfer performance of glass-water/ZGM thermosiphon at room temperature. According to the experiment results, this paper fabricates a copper-water/ZGM thermosiphon, and based on this, it designs a siphon heat pipe vacuum solar water heater. The research results show that the optimal liquid filling rate of the glass-copper thermosiphon is about 14%. Compared with water, for thermosiphon with ZGM as the working medium, the temperature of each point is about 2°C higher. The glass-water/ZGM thermosiphon has good isothermality and thermal conductivity, and the start-up temperature is low, about 14°C. The research results of this paper have important guiding significance for the improvement and optimization of solar water heater systems.