To improve the walking energy efficiency and dynamic balance performance, the innovative lightweight design of robot calf was proposed with the help of topological optimization technology, and the calf assembly structure was redesigned as an integrated structure, reducing the parts from 11 to 1. Besides, with the help of laser powder bed fusion technology, AlSi10Mg was selected as printing material to carry out the additive manufacturing process research. Using Altair Inspire software to carry out laser powder bed fusion process simulation, and the optimized laser process parameters window was obtained, line energy density was 90~210 J/m. On this basis, the finished product was printed, finally realizing the goal of calf weight reduction up to 63.8%.