[en] The Beishan area, a Gobi desert in Gansu province, is considered as a suitable candidate for high-level radioactive waste (HLW) geological repository in China. The dominant lithology in Beishan area is porphyritic monzonitic granite, with coarse-grained pegmatite dikes distributed locally and tonalite enclaves or veins. The porphyritic monzonitic granite has high isotropic. The deep intact rock of Beishan area has low water content, low water sorption, low porosity, high unconfined compression strength, high shear strength, high tensile strength and low strain. Triaxial compression strength and strain of the rock increase rapidly as the confining pressure increase. The crack damage stress decrease with the temperature increased from room temperature to 90℃, The time to failure increases rapidly as the constant load decreases. At the same constant load, the time to failure reduces when the temperature increases. (authors)