The invention discloses a method for producing high-purity carbon granules from waste carbon blocks in an arc furnace, which comprises the steps of pretreatment, preparation and after-treatment, and specifically comprises the following steps: crushing the raw material waste carbon blocks, and screening to obtain waste carbon block granules; and adding the obtained carbon block granules into a direct-current arc furnace, electrifying to start arc, taking out, and cooling to obtain the target substance high-purity carbon granules, wherein fume generated by combustion enters a dust collecting system to be collected and recycled. The method has the advantages of simple technique and obvious environmental benefit, and uses waste in urgent need of treatment as the raw material; the whole production procedure adopts a dry process, and thus, does not generate wastewater; various resources are completely recycled, no that no waste is generated; and the gas is completely collected and purified, and thus, the environmental pressure is low. The fixed carbon content can reach 99% above, the ash content is less than 1%, the total sulfur is less than 0.5%, and the low heat value on air dry basis is greater than 8000 calories/g; and the high-purity carbon granules with the graphitization degree of higher than 80% have favorable electric conductivity,, favorable thermal conductivity, high stability and high heating value, and thus, are a favorable raw material for various graphite products and metallurgical industry.