Abstract: The utilization of energy has become the current hotspot with the development concept of energy saving. This article studies the 3-d numerical simulation of heat transfer process for multi-start spiral pipe by using the light pipe with equivalent diameter as the benchmark tube. The heat transfer process of models is simulated through the ANSYS, obtaining the distribution of the temperature and flow field in the heat transfer process. The results are analyzed comprehensively by the boundary layer theory and collaborative field theory in heat transfer. The results show: the heat transfer performance of multi-start spiral pipe is significantly better than that of the light pipe with the same heat flux. In comparison with the light pipe, the exit temperature of the fluid for the multi-start spiral pipe is increased to 2.6 times and the exit speed is reduced to 50 ％. The main reason of heat transfer enhancement lies in its internal and external rib structure. The walls of multi-start spiral pipe are not liable for scaling for fluid vortex flow due to its rib structure.