In order to obtain the mechanical properties of the 1，3，5-triamino-2，4，6-trinitrobenzene（TATB） granules， an in-situ micron-level mechanical loading device suitable for X-ray Micro-Computed Tomography system was designed. By using the X-ray Micro-Computed Tomography technique， the structural characteristics were non-destructively characterized. Hertz contact model was used to study the force-displacement relationship of the individual granule. Mechanical properties of granule such as Young"s modulus， yield point， contact stiffness， breakage force， and structural characteristics of granule such as particle shape， pore shape， pore distribution were determined. The results show that the quasi-static normal compression process of a single TATB granule has three stages： elastic deformation， elastic-plastic deformation， and collapse. The pores with small size and dispersed spatial structure in the granule do not change during the particle deformation process， and the large sheet-like pores inside granule paralleled to the loading direction significantly reduce the breakage strength of the particles. The difference in the internal structure of the particles has large influence on their compression mechanical properties significantly.