Abstract: To control deformation of the support structure of dry disc brake, a topology optimization design model was proposed. Firstly, based on the variable density method, an optimization model was established with the minimum displacement of the key control points of the supporting structure as the objective function. It was arranged to control the deformation of the key position of the support structure by setting the minimum distance between the key point and its corresponding target coordinate. And then the weighting factors of key points were used to highlight the primary and secondary relationship of optimization objectives. The topological configuration of the supporting structure in three different design domains was analyzed, and the influence of constraint conditions on the topology optimization structure was studied. Finally, a composite hole and groove structure was designed for the support structure optimization pillar with a triangular-like through hole in the lower right corner and a larger shallow groove structure on the outer surface. The results show that as the volume reducing, the maximum deformation and maximum stress of the support structure will increase accordingly. In the case of the maximum displacement unchanged, the volume of the optimized support structure finally obtained can be reduced by 10.2%. In the case of the same volume, the maximum displacement can be reduced by 9.4%. When the volume is reduced by 6.0%, the maximum displacement can be reduced by 4.1%.