Abstract: On field survey and points sort in Li Jiahao Mines for coal gangue，coal gangue rock of different abandoned times in-situ shear test and indoor large shear test，analyzes the corresponding experiment of coal rock mass shear stress，shear displacement curve，the peak shear stress was calculated under different stress level of shear strength，combined with the rock strength criterion on Hoek Brown - cohesion and internal friction Angle of the test results were discussed. The results show that the longer the disposal time of gangue，the better the cementation of gangue block，and the later the peak strength of gangue rock mass，the greater the shear strength. In the pre-peak strength stage，with the increase of shear stress，the shear deformation of gangue is mainly elastic deformation. The cohesion and internal friction Angle of gangue in situ shear test are both larger than that of large shear test，the cohesion value estimated by Hoek-Brown rock mass strength criterion is larger than that of test，while the internal friction Angle estimation is close to that of test. It provides a reference for the future study of the shear characteristics of gangue rock mass and the stability analysis of gangue rock slope.