<正> This paper presents a method for analyzing bothlinear and nonlinear seismic responses of multi-storeyed buildings composed of nonorthogonal struc-tural members under the action of bi-directional ho-rizontal earthquake waves. Different kinds of re-storing force model are used. An efficient computerprogramme for the computation of nonlinear seismicresponse of the structure was worked out. In order toillustrate the application of this method,an exampleof a ten-storeyed building of such sort is given.