Abstract: In order to improve the stress of bamboo fibers in the tension zone, preimpregnated fiber sheets(fiber-reinforced polymer, FRP)were placed in the tension zone of bamboo beams, in which the good tensile properties of FRP was utilized to enhance the flexural performance of bamboo beams. Five bamboo beams were tested under flexural loading to investigate the mechanical behavior for FRP reinforced beams, in which one control bamboo beam and four FRP-reinforced bamboo beams were involved. The main parameters include the types and layers of FRP. Test results indicate that FRP can improve significantly flexural performance of bamboo beams, in which the flexural bearing capacity and the stiffness are effectively enhanced. Comparing with the control bamboo beam, the load-carrying capacities and the cross-sectional stiffness of the FRP-reinforced bamboo beams increase by 30.16%-52.44% and 9.73%-12.89%, respectively. Due to the loss of adhesive, basalt fiber has better strengthening effect in bearing capacity, while carbon fiber has better strengthening effect in cross-sectional stiffness for higher elastic modulus. Moreover, the strain profiles demonstrate the strengthening roles of FRP in bamboo beams.