Abstract: In order to investigate the horizontal storey shear distribution of a steel plate shear wall under an elastic-plastic state, a total of four SPSW structures with ideal yield mechanism were designed. The effects of story number, velocity pulse near-fault records and acceleration cumulative effect far-fault records were considered. The average story shears of SPSW structures under two kinds of earthquake records were obtained through a nonlinear time history method. The formula of elastic-plastic story shear of SPSW was proposed, and the existing horizontal shear distribution pattern was compared. Near-fault records with velocity pulse and far-fault records with acceleration cumulative effect had important effects on the story shear distribution of SPSW, and this effect factor should be taken into account. The story shear distribution proposed by this paper was more accurate than other story shear distribution patterns. The story hysteric energy of SPSW can be computed reasonably through this new proposed story shear distribution pattern in the energy based aseismic method.