Abstract: This study aims to investigate the high modal effects on the seismic performance of Self-centering Dual Rocking Core (SDRC) systems and the force demands of rocking core structural members. With the consideration of high mode contribution, a performance-based design procedure for the multi-storey and high-rise SDRC systems was proposed under the theoretical framework of the direct displacement-based design. The formula for the calculating the shearing force of the base design of the SDRC systems was derived. Based on the proposed design procedure, a 12-storey SDRC system was designed and some comparison cases were also designed upon the existing design method. The seismic performance and nonlinear behavior of the designed systems under near-fault and far-fault ground motions were analyzed via one static pushover analysis, one dynamic analysis, and one time-frequency domain analysis. The analysis results demonstrated that the proposed design methodology can be used to design multi-storey SDRC systems. The existing design method applicable to low-storey SDRC systems is no longer applicable to the design of multi-storey SDRC systems. High modal effects can magnify the force demand of structural members in the rocking cores. The developed design method can provide a reasonable reference for the design of structural members. The high modal effects will be more significant with the increasing intensity of ground motions. The near-fault ground motions have richer high-frequency contents, leading to more significant high modal effects on the structure.