As a promising development for seismic resilience, this paper addresses the urgent need for earthquake-resistant construction methods, focusing on developing a new brace called the “Channel steel- I-section Buckling Brace” (CI-BB). The design combines replaceable low-yield wide flange steel for the cores with high-strength channel steel as constraining parts. Moreover, it offers insights into restraining channel steel and the complex deformation patterns in low-yield I-section steel core components during earthquakes. The primary role of the wide flange section core was to dissipate energy, while channel steel remains elastic and thus provides strength and withstand loads. This study first introduces the design concept and formulations of the low-yield I steel to estimate the yield strengths, stiffness, and axial displacement of the brace at various stages of loading. The application of this concept was proved through an example following the given formulations. Finally, a finite element analysis studied the numerical model subjected to various cyclic loading to examine the seismic performance of the proposed CI-BB. Consequently, the results show that the proposed CI-BB is stable and robust, able to withstand significant axial loads without losing stiffness.