Concrete-filled fiber Tube(CFFT) is gaining prominence as a feasible alternative for a va-riety of structural applications. Even though the structural performance of CFFT beams is undeniable and their use in industry and research is growing, an extensive experimental and numerical study of these beams has not been undertaken recently. Hence, more re-search is required to better understand the flexural response of prestressed rectangular CFFT beams. The effects of PT tendon eccentricity, non-prestressed reinforcement ratio (As/bh), prestressed reinforcement ratio (Ap/bh), and the tube structural laminate of GFRP modeled using normal strength concrete(NSC) and high-strength concrete(HSC) were investigated. In this study, Thirty-four quarter-symmetric FE models were built in the ANSYS APDL with appropriate boundary conditions at the symmetry plane and support to get the same response as the full-scale experimental beam found in the literature. The sensitivity analysis was performed with seven different mesh densities to determine the best element size that accurately depicts the load-deflection behavior of numerical models. The results revealed that both NSC and HSC-filled PT CFFT have similar plastic nonlinear responses. Increasing the prestressed and non-prestressed reinforcement ratio of PT CFFT beams significantly improved the overall performance of PT CFFT beams as compared to other investigated parameters. Placing the PT tendons at the bottom of PT CFFT beams enhances the cracking, yielding, and ultimate load carrying capacities by 7.98%, 12.32%, and 9.03% for NSC-filled PT CFFT beams, respectively. Doubling the axial stiffness of the tube laminate structure increased the ultimate load, Energy absorption capacity (EAC), Pre-yielding stiffness (Kpre), and Post-yielding stiffness (Kpos) by 18.5%, 12.15%, 9.21%, and 8.2%, respectively for NSC-filled PT CFFT beams. Straight PT tendons increased in cracking, yielding, and ultimate load capacity by 10.85%, 14.6%, and 13.58% more than the curved profile tendons. The ductility of PT CFFT beams is more sensitive to the amount of prestressed reinforcement ratio and the effect of other investigated parameters was neg-ligible. In all the parameters investigated increasing concrete strength by 75% showed min-imal impact on the structural performance of PT CFFT beams. It is strongly suggested that additional research be conducted to investigate the flexural behavior of PT rectangular CFFT beams for high percentages of prestressed and non-prestressed reinforcement ratios as well as other significant parameters not covered by this work. Keywords: Flexural behavior, PT CFFT, ANSYS APDL, GFRP