Abstract: Based on a shearing storey model and a hysteretic model of cold-formed thin-walled steel stud walls, the simplified calculation of the elastoplastic displacement for cold-formed thin-walled steel buildings is studied by the elastoplastic time history analysis on two-storey buildings to seven-storey buildings . The weak storey is suggested by analyzing the distribution of hysteretic energy in the height of a storey. The influences of storey yielding shear force factors, storey numbers, fundamental periods of structures and different seismic records on elastoplastic displacement amplification factors are studied. The quantitative relations among storey yielding shear force factors, storey numbers and elastoplastic displacement amplification factors are proposed to estimate the elastoplastic displacement for cold-formed thin-walled steel buildings under rare earthquakes.