The parallel target positioning system is a new type of target positioning system used in the inertial confinement fusion (ICF) .The heat balance equation of the system is established based on analysis of principle of parallel target positioning system and heat transfer path. By analyzing the heat source in theory and experiment, heat output power and temperature are determined. The temperature of the key parts of parallel target positioning mechanism is gotten by thermal analysis, which provides a theoretical basis for the design and accuracy analysis of the parallel target positioning system.