Abstarct: Corrosion in reinforced concrete structures reduces the bearing capacity and the ductility of the concrete members and elements. The use of fibers to improve the mechanical properties of concrete has been attented by engineers. In this study, an experimental program was done to investigate the effect of macro polymer fibers and steel hooked fibers on corroded and non-corroded reinforced concrete beams and then reinforced by GFRP. Two types of fibers called macro polymer fibers and steel hooked fibers with volume percentages of 0% and 0.5% were tested at three approximate corrosion levels: 0%, 7% and 9%. A pool of 3% salt was used for accelerated corrosion test. Finally, the reinforced and unreinforced concrete beams were subjected to bending loading experiment. The structural behavior of reinforced concrete beams in corroded and non-corroded beams with and without fibers before and after retrofitting was investigated. According to the experimental results, corrosion decreases the ductility of the samples and the use of steel hooked and macro polymer fibers in the samples with no corrosion and with corrosion in level one and two leads to a doubling of the ductility. Macro-polymeric fibers had a greater effect on increasing the ductility of the specimens than steel hooked fibers. Increasing the corrosion percentage in the samples without fibers decreased the maximum strength of the samples but in the samples with fibers by increasing the corrosion percentage no significant change was observed in the bearing capacity of the samples. using of GFRP, increases the ductility and bearing capacity of the specimens and reduces the number of formed cracks and decreases their depth and the focuse of damage will be near the separation zone.