Concentrically braced frames are among the most common systems due to ease of implementation and low cost compared to the moment resisting frames, however non-ductile behavior after buckling of compression element is noticeable. So, various research projects have been conducted to deal with this shortcoming. In this paper, the effect of steel angle in slit brace is considered to prevent its buckling. Stresses and displacement of structures using nonlinear static analysis by finite element software "ABAQUS" are evaluated. Results indicate improved cyclic performance and ductility of CBF systems. In addition, comparing the hysteresis loop of the proposed sample with that of normal braces shows symmetric and stable rational behavior where strength and stiffness degradations are not observed in the displacement up to about 3 cm while the normal brace buckles in about 1 cm.