An　analytical　model　for　the　preliminary　seismic　design　of　high-order　buildings　with　multi-lateral　structures　is　developed.　A　high-rank　differential　equation　group　is　established,　with　which　the　reciprocal　action　among　the　lateral　structures　can　be　decoupled.　Comparison　is　done　between　the　calculated　results　of　this　model　and　another　FEM　model　developed　via　ANSYS.　The　model　and　the　suggested　calculation　method　can　be　used　to　judge　the　reasonable　structural　layout　in　the　stage　of　preliminary　seismic　design.