To design reinforced concrete structures in seismic regions, it is essential to understand the behavior of these structures under inverse cyclic loading. It is imperative that they demonstrate sufficient local and global ductility. Consequently, ductility is a critical consideration in contemporary seismic design practices. In reinforced concrete columns and beams subjected to seismic loads, failure is frequently initiated by the buckling of longitudinal bars, which is preceded by the spalling of the concrete cover. To accurately simulate the nonlinear response of reinforced concrete structures, it is essential to employ a suitable material model for the reinforcing bars that incorporates the effects of buckling. Modeling the performance of cyclically loaded reinforced concrete structures is a labor-intensive process, necessitating the use of complex models for both concrete and steel that account for repeated loading, unloading, reloading, and the reversal of load direction. This paper introduces a novel model for cyclically loaded reinforcement, incorporating considerations of inelastic buckling. In this model, the stress–strain relationships are defined solely for the envelope of the hysteresis loop. It has been determined that only two mechanical parameters of steel, yield strength and ultimate strength, are required to accurately describe the constitutive relationships. The predictions of bar behavior derived from this model align closely with experimental results. The proposed model for the overall behavior of a cyclically loaded bar can be effectively applied to the analysis of reinforced concrete frame structures.