Taking the manufacturing of high-pressure turbine guide for a spaceflight power system as an example, in view of the short - term problems in the manufacturing process, from the aspects of material characteristics, structural characteristics and technical requirements, the causes of the problems were analyzed. From the aspect of thermal gap control, the thermal deformation control technology of multi-degrees of freedom space structure under high temperature brazing was studied, and the actual application and verification of the research results were carried out based on the production and manufacturing of power system. And the following conclusions: through the clamping device to control the hot deformation, the pressure part closer to the welding position, the better effect; During the brazing process, after the completion of the heating phase, because of the penetration of filler metal, the two parts become one, and in the cooling stage, with the same center retracting, at this time the most gap has been filled by filler metal, so the clearance can not change; Under the condition that the cold space meets the technical requirements, the thermal expansion deformation under high temperature will lead to a large gap. The solder began to melt at about 997℃ . The flow velocity and clearance can not be controlled by heat treatment system, and the temperature change in small range is very small. A set of thermal deformation control methods suitable for the spatial structure of multi-degree of freedom is summarized.