Based on the fatigue test for flexural performance of reinforced concrete beam strengthened with aramid fiber reinforced plastic(AFRP),the effect of fiber layers on the fatigue test performance of the strengthened beam was analyzed according to the strain cycling curve of steel and the stiffness reduction regularity of the beams. The fatigue test results illustrate that the bonded AFRP can improve the fatigue performance of the strengthened beams, enhance the service life of the reinforced concrete structures, which testified the validity and feasibility of this technology in the field of structure strengthening.