Abstract: Loop heat pipe can be used on the photon absorber to improve its heat exchange efficiency and reduce its structural size, and for vibration-free operation, so it is an important technical reserve for the future design of photon absorbers in high-performance accelerators. The heat transfer performance is analyzed when the loop heat pipe is applied to the photon absorber, the results show that the current heat transfer capacity of the loop heat pipe fully suffice the requirements of the photon absorber, but the structure of the heat sink, especially the heat transfer distance, needs to be strictly optimized. Then, using the type “C18” loop heat pipe made by China Academy of Space Technology, a prototype of the photon absorber heat extracted by loop heat pipe was designed and optimized, the temperature distribution is simulated numerically, and the heat transfer capacity was tested experimentally.