By using a CBN synthesis catalyst containing a CBN synthesis catalyst component coated with an organic substance for producing cubic boron nitride (CBN), the CBN can be produced at a high transformation ration and a high yield ratio. Each of the CBN grains produced through this method has a sharp shape with a highly developed (111) plane, exhibits high strength, and exhibits a small reduction in strength due to heating. The amount of catalyst component contained in the CBN is 7.5.times.10.sup.-4 mol or less per 1 mol of CBN.