The invention discloses a system and a method for preparing porcelain balls from chromium iron slag. The system comprises a mixing device which has a molten chrome iron slag inlet, an alumina materialinlet and a mixed slag outlet; a granulation device which has a mixed slag inlet and a first pellet outlet, wherein the mixed slag inlet is connected with the mixed slag outlet; a consolidation device which has a first pellet inlet and a second pellet outlet, wherein the first pellet inlet is connected with the first pellet outlet; and a screening device which has a second pellet inlet and a porcelain ball product outlet, wherein the second pellet inlet is connected with the second pellet outlet. The system uses the molten chrome iron slag and a waste alumina material as raw materials to prepare the porcelain balls, can make full use of the sensible heat of the chrome iron slag, has significant energy-saving and consumption-reducing effect, and realizes the recycling and harmless utilization of the chromium iron slag and the waste alumina material.