The invention discloses a cubic boron nitride blade and a preparation method thereof, and belongs to the field of super-hard cutting tools. The cubic boron nitride blade is prepared by using cubic boron nitride, bonding agent, abrasion and damage resistant agent and adhesive as raw materials. The preparation method comprises the following steps of: (1) performing level matching heating on the cubic boron nitride, and then adding the bonding agent, the abrasion and damage resistant agent, the adhesive and densifying agent; (2) blending the substances in the step (1) under the atmosphere of argon or nitrogen, and heating; and (3) mechanically pressing the materials obtained in the step (2). The micro and nano cubic boron nitride and the matched micro and nano bonding agent, abrasion and damage resistant agent, adhesive and densifying agent are used as raw materials; in the high-temperature and high-pressure sintering process, the adhesive and the densifying agent enable the polycrystal sintering to be compact, and the bonding agent and the abrasion and damage resistant agent endow the blade with high hardness and abrasion resistance; and the integral polycrystal cubic boron nitride sintered blade with high abrasion is produced.