Different formations can be encountered in drilling engineering. According to the physical and mechanical properties they are classified as isotropic and anisotropic ones. And in most cases they are anisotropic due to the influence of complicated geological conditions. One of their features is different hardness in different directions of loading， leading to borehole deviation， hence compromising drilling rate and quality. Russian researchers have done a lot of research on drill bits and downhole devices used for drilling in the anisotropic formations and good results have been obtained which can provide reference for us in deep drilling.