Abstract: Based on the P-wave velocity test,CT scanning and three-dimensional reconstruction technology,the distri- bution heterogeneity of cracks and mineral inclusions in coal sample,obtained from the No． 14 coal in Xinzhou Mine, was researched,and the failure characteristics of coal samples loaded in different directions effected by its heterogenei- ty were also investigated,according to the uniaxial experiment when the coal samples loaded in various directions. Re- sults indicate that the distribution heterogeneity of microstructures in coal sample leads to the difference of failure char- acteristics loading in different directions. The primary fractures and mineral inclusions are distributed and extended along the bedding plane,the average uniaxial compressive strength,total AE count,and other parameters are loaded perpendicular to bedding plane higher than that parallel to bedding plane,at the same time,the transverse cutting effect of cleats makes the parameters of mentioned above and the regularity of AE in the loading process loaded per- pendicular to cleats lower than the coal samples been loaded parallel to the cleats. The UCS and the P-wave velocity of the coal sample have an exponential function relation,and the effect of heterogeneity inside the coal sample on the UCS can be reflected by the heterogeneity coefficient,and the heterogeneity coefficient has a negative correlation with the UCS of the coal.