The invention discloses an operating technology of a sludge-free slag melting furnace with low power consumption. The technology comprises the following steps that (1) preparation is made before slagmelting; (2) fractional operation and ordered material adding are performed, specifically, arcing operation is performed, and three hoppers of slag materials are added; (3) lime is added, specifically, the lime is added into the furnace in three stages according to the rhythms of slow, quick and slow correspondingly; and (4) bull ladle conditions are confirmed, and the conditions include the slagtemperature, the ladle bottom thickness and the ladle interior foam amount. According to the operating technology, by means of the slag melting furnace quick arcing method, the production efficiency is improved; due to the adding sequence of the three hoppers of the slag materials and the lime adding method, the power consumption is reduced, and the sludge phenomenon is reduced; and since the bullladle conditions are confirmed, damage of a thick ladle bottom to slag components is avoided, the number of production quality accidents caused by deviation of the slag components is decreased, lossis reduced, and the benefit is remarkable. By means of the technology provided by the invention, the occurrence rates of sludge and the thick ladle bottom are decreased greatly, the power consumptionof the slag melting furnace is lowered by 5.2-6.3 kWh for per ton of steel on average, and the electric slag remelting ingot flaw detection qualification rate reaches 98.23-98.28%.