Abstract: In order to study the shear mechanical properties of anchored rock mass under impact load,the lateral impact tests under different impact energy and pretension torque were carried out on the anchored rock mass of two kinds of bolt materials by using the laboratory test method,the effects of different bolt materials and pretension torque on the shear mechanical properties of anchored rock mass under impact load were analyzed,and the time history curve of drop hammer impact force was monitored. The whole process of impact deformation of the sample was captured by a high-speed camera. The test results show that the impact process of the anchored rock mass can be divided into three stages:drop hammer release,hammer rock downward movement and separation rebound. There are axial shear cracks and accompanying vertical cracks on the top and bottom of the sample. The front and back are abdominal shear oblique cracks and vertical cracks. The interface cracks are distributed radially around the borehole,and the number of cracks in the upper part is significantly more than that in the lower part,and the crack width is mostly within 10 mm. In a certain range,the damage degree of the top surface and interface of medium block concrete increases with the increase of impact energy and decreases with the increase of pretension torque. The bolt will bend,shrink or even break under dynamic shear. In a certain range,the greater the impact energy is,the greater the bending deformation of the bolt is. The greater the pretension torque is,the stronger the impact deformation resistance of the bolt is. The impact deformation and breaking capacity of the CRM700 bolt are better than that of the HRB500 bolt,which can significantly improve the overall impact resistance of anchored rock mass. According to the time history curve of impact force,the impact process can be divided into strong impact stage,oscillation stage and attenuation stage. The time of the strong impact stage is only about 1 ms,mainly due to the contact between the hammerhead and the sample. The duration of the vibration stage is about 10 ms,which mainly occurs the fracture failure of concrete block and the bending deformation of the anchor bolt. On the whole,the bolt material and pretension torque have a significant impact on the shear mechanical properties of anchored rock mass under impact load. The use of a CRM700 bolt or the application of appropriate pretension torque can improve the shear mechanical properties of the anchored rock mass.