The initial structure of coarse-grained soil has a great influence on its macroscopic shear strength and the strength evolution during shearing. In order to study the initial structural strength of coarse-grained soil and the contribution of the initial structure to the shear strength in the shearing process, a visualized direct shear apparatus was used to investigate the shear stress value contributed by the initial structure of the particles in the macroscopic shear strength of the soil. It is concluded that the shear stress resisted by the initial structure of the coarse-grained soil accounted for about one-third of the overall shear strength. Then the variations of the particle initial structure characteristic indices, such as particle shape, arrangement and contact relationship were analyzed before and after the initial structure was deconstructed, and the influence weight of each index on the initial structure effect was evaluated and ranked using AHP -weight entropy method. The results show that the particle contact relationship had the greatest influence on the initial structure effect, and its weight accounted for 42.66%, followed by the overall particle profile coefficient, which accounted for 26.02%.