“In the field of deep space exploration, the power supply of heat pipe nuclear reactors has become a research hotspot due to its passive nature, long lifespan, and high reliability. This article focuses on the research of heat pipe power systems, Mars exploration reactors, safe and affordable fission engine solutions, and Kilopower. It summarizes their structural design, fuel selection, heat pipe layout, and power design, providing ideas and references for the future design of heat pipe space nuclear reactor power sources.”