In order to study the cyclic shear characteristics of fiber reinforced granite residual soil, polypropylene fiber was incorporated into the residual soil. The horizontal cyclic simple shear test of fiber reinforced residual soil was carried out by dynamic simple shear apparatus. The effects of different fiber content ( 0,0.3%, 0.6%, 0.9% ) and cyclic stress ratio ( 0.15,0.20,0.25,0.30 ) on the dynamic characteristics of granite residual soil were analyzed. The test results show that with the increase of cyclic stress ratio, the dynamic shear strain increases. The addition of fiber effectively inhibits the development of dynamic shear strain of residual soil, and the higher the fiber content, the smaller the dynamic shear strain. The fiber increases the critical cyclic stress ratio of the residual soil. Under the critical cyclic stress ratio, the number of cycles when the reinforced sample is destroyed is much larger than that of the unreinforced sample, which indicates that the addition of the fiber increases the toughness of the soil and greatly delays the failure time of the soil sample. The dynamic shear modulus and damping ratio decrease first and then remain stable with the increase of the number of horizontal cycles. Under the same cyclic stress ratio, the larger the fiber content, the greater the dynamic shear modulus and damping ratio. For the dynamic shear modulus, the smaller the cyclic stress ratio, the more obvious the advantage of fiber reinforcement. The improved H-D model can be used to analyze the dynamic response of granite residual soil under different cyclic stress ratios and different fiber contents.