This paper, combined the characteristics of steel structure and timber structure, conceives a new system of residential structures—staggered truss steel-timber combined structure, carries out structural arrangement and optimization design on a six-layer residence, and makes a study on its seismic performance under rare earthquake. The author uses commercial structural analysis softwareto establish a basic model, conducts pushover analysis, draws the load-displacement curve, then getsthe capacity spectrum of the model, next compares with the demand spectrum under 8 degrees (0.3g)rare earthquake, finally gets the performance point of the structure. The results show that the inter-story displacement angles can meet the limit of seismic code. Meanwhile auther analyzes the distribution and the appearance sequence of plastic hinges, plastic hinges mainly occur in the truss webs, the chords and the frame beams in succession, and the number of plastic hinges is more. Bottom columns finally appear plastic hinges. These phenomena meet the design requirement—strong column-weak beam.Finally this paper gets a conclusion that staggered truss steel-timber combined structure shows good seismic capacity.