Abstract: Future interstellar navigation will demand new energy. The thrust of spacecraft using chemical fuels is difficult to sustain, and a suitable launch window must be found for each launch in order to utilize the planet’s gravity for acceleration. Traditional solar panels are far from meeting the energy requirements for manned interstellar travel and must rely on the effective and stable supply of new energy power systems. The propulsion system of new energy powered spacecraft can carry a larger payload, enter planetary orbit and return to the ground in a more flexible and efficient manner, but also poses higher requirements for waste heat dissipation at high temperatures. Heat pipe technology is an important technical means to achieve efficient and long-distance heat transfer in medium and high temperature zones (100～300℃). The current radiator design increasingly relies on heat pipes. Titanium water heat pipes with high thermal conductivity at high temperatures can effectively transfer heat and raise the radiation temperature, thus minimize the area of the radiator. Experiments and simulations on the 3D printed titanium water heat pipe were conducted. Applying different heating powers at 100～225℃, the heat transfer capacity of the titanium water heat pipe was studied. The results show that the maximum heat transfer temperature difference of the titanium water heat pipe increases with the increase of heating power. The maximum heat transfer power of titanium water heat pipe at 200℃ is 893.9 W, and analysis shows that the maximum heat transfer power of titanium water heat pipes is greater than 893.9 W at 200～264℃. Based on experiments, simulations were conducted to obtain the variation of the equivalent heat transfer coefficient of titanium water heat pipes with temperature. The equivalent heat transfer coefficient at 250℃ is predicted to be 3650 W·m^–2·K^–1, with a heat transfer temperature difference of 29.22℃.