n the last few decades, Fiber-Reinforced Polymers (FRP) bars have emerged as alternatives to conventional steel reinforcing bars to overcome the corrosion problem found in reinforced concrete structures. Fiber Reinforced polymer (FRP) is a new material, so it is necessary to identify the differences and limitations of their use in the concrete structures in relation to traditional steel reinforcement of concrete structures. Numerous studies have been conducted in order to evaluate the bond between FRP bars and concrete. This paper presents the test results of a study on the bond behavior of simply supported beams under flexure, reinforced with FRP bars (BFRP and GFRP) compared to the reference beam with steel reinforcement. The tested beams were made of C 40 concrete and reinforced with bars with 10 mm diameter having and tensile strength evaluated from the tensile tests. The analysis of the beam deflection behavior has been presented. The results show the different character of the load-deflection relationship of FRP reinforced beams compared to traditionally steel reinforced beams.