This study quantified the anisotropy of element composition in Upper Triassic "Chang 8" shale in Jiyuan district of Ordos Basin, China and provided the microscopic evidence for the existence of dominant fracture zone. Element quantification was carried out ensuring both observational resolution and sample representativeness. Results show that for shale slices in two directions which are 45 degrees (225 degrees) and 0 degrees (180 degrees /360 degrees), the distribution of elements is significantly different from that in other directions. The minimum of element contents often occurs in 45 degrees (225 degrees) and the maximum of element contents often occurs in 0 degrees (180 degrees/360 degrees). The brittleness parameter value stays at a high level from 0 degrees (180 degrees/360 degrees) to 22.5 degrees (202.5 degrees). The maximum value occurs in 0 degrees (180 degrees/360 degrees), and the minimum value occurs in 45 degrees (225 degrees) which has obvious significance in shale stimulation. The conclusion proved that the existence of predominant fracture zone in shale has the microscopic evidence in micro-scale brittle minerals.