In geological drilling and petroleum drilling, the bit is a very important drilling tool. Its technical characteristics, particularly its hardness and wearresistance, is related directly to drilling technical and economical index, i.e. penetration rate, bit footage and drilling cost per meter. In order to improve performance of the bit, South Russian State Technical University has proposed and tested cryogenic nitrogen and magnetization integrative treatment method for the bit. The hardness of the bit body, base of PDC and the solder layer were improved by 30%, 3% and 22% respectively. The field testing results show that the penetration rates of the bit with the treatment of cryogenic nitrogen and magnetization were improved than those of the normal one in each test, and the penetration rate of this type bit increased by overall 222%, achieving good results. Meanwhile, the obtained results were analyzed with Xray diffraction and electronic microscopic technology.