The invention discloses a preparation technology of super pure coal, and is applicable to the technical field of mineral separation. The preparation technology comprises the steps that after minus 50 mm low-ash anthracite is crushed through a high-efficiency fine crusher, the crushed low-ash anthracite is introduced into a three-product interference bed for separation, and coarse clean coal, medium coal and recrement are obtained; coarse clean coal is classified through a three-product vortex sieve, and coarse clean coal remaining on the sieve is dehydrated through a coal slime centrifuge to obtain a coarse-particle super pure coal product; and after primary coarse grinding, medium coal is introduced into a sieve bend for classification, oversize material on the sieve bend is introduced into a spiral separator for tailing discharging, and after secondary fine grinding, a light product is introduced into a flotation device for flotation together with screen underflows of the three-product vortex sieve, overflows, the centrifugate of the coal slime centrifuge, and screen underflows of the sieve bend, and a fine-particle super pure coal product is obtained. According to the preparation technology, a two-stage ore grinding technology is adopted, so that an overgrinding phenomenon which often occurs during open-circuit grinding is avoided; tailings are discharged during primary ore grinding, so that efficiency and energy consumption are achieved; the two-stage floatation is adopted, so that low-ash clean coal can be obtained; and compared with a traditional separation technology, the preparation technology has the advantages that the principle of more crushing and less grinding is better met, efficiency and energy consumption are achieved, and the economic benefits are remarkable.