To satisfy the lightweight design requirements of the thin-walled titanium sensor brackets of small satellites, the topology optimization method is to manufacture sensor brackets by 3D printing. The topology optimization constraint conditions are the stiffness no less than 200 Hz and the minimum bracket weight. The material distribution model is generated after topology optimization. The shape optimization and morphology optimization method are used to smooth the material distribution, and the sensor brackets with optimized topology are produced. A finite element analysis demonstrates that the mechanical stiffness and strength of the designed sensor bracket meets the requirement. The sample piece is manufactured by Ti6Al4V(TC4) laser selective melting (SLM) and the manufacturability is verified. The weight of the designed bracket is 80% lighter than the thin-walled titanium casting bracket.