Glass fiber-reinforced-polymer (GFRP) bars are increasingly recognized as being suitable as the primary reinforcement in concrete structures. In recent years, many researchers have been studying their seismic performance as a lateral resisting system. Because of the lack of experimental data, GFRP bars are still not recommended for seismic design. Given the need for comprehensive seismic-performance assessment, hysteretic models must be developed depending on GFRP bar properties. The primary purpose of this study was to identify the various parameters controlling the hysteretic response of GFRP-reinforced shear walls. Six fullscale specimens reinforced entirely with GFRP bars were recently constructed and tested under the combined action of reversed cyclic lateral load and constant axial load. The test results show stable performance and an acceptable level of deformability. An analytical model was developed using the experimental results for correlation, aiming to reproduce the hysteretic response. The model was achieved by investigating the parameters that control the hysteretic response and studying their effect on the deterioration rate. The cumulative dissipated energy, the cyclic distortion due to stiffness degradation, and the idealized load-displacement curve were analyzed. The proposed model was compared with the experimentally generated response and simulated the hysteretic response of GFRP-reinforced shear walls with acceptable accuracy.