A CBF frame is an earthquake-resistant system used in steel structures. The brace of this system can be used in various shapes, such as X-shaped, V-shaped, elbow, etc., each of which can change the behavior of the structure. However, low plasticity, high hardness, absorption, and low seismic energy consumption are among the disadvantages of this system. A seismic design should be such that the structure remains in a linear range without damage during small earthquakes. It will suffer non-structural damage in moderate earthquakes, and it will have structural and non-structural damage during severe earthquakes, but its stability will be maintained with a proper design. The brace can also be quickly and economically modified and strengthened after the earthquake damage. The literature has shown that the use of arc or ellipse braces can act properly in transferring lateral forces and improve the behavior of the structure. In this research, therefore, four models of CBF frames with arch braces in different shapes are proposed to investigate their seismic behavior in a two-story structure. The models designed by the finite element method were subjected to lateral and cyclic loading to compare their bearing capacity, seismic behavior, ductility, seismic energy consumption, behavior coefficient, stiffness reduction, failure mode, and economic index. A summary of the results shows that the use of ellipse braces in the two-story structure can be more compatible with the purpose of this research.