The present invention relates to slurry for polishing crystalline phase-change materials and to a method for producing a phase-change device using the same. The slurry for polishing crystalline phase-change materials according to one embodiment of the present invention comprises an abrasive, an alkaline abrasive enhancer, an oxidizing agent having a standard reduction potential higher than that of perchlorates, and ultrapure water. In addition, the method for producing a phase-change device according to one embodiment of the present invention comprises the following steps: preparing a substrate; forming a crystalline phase-change material film on the substrate; and removing the phase-change material film through a chemical-mechanical polishing process using slurry for polishing phase-change materials, which comprises an abrasive, an alkaline abrasive enhancer, an oxidizing agent having a standard reduction potential higher than that of perchlorates, and ultrapure water.