Abstract: The bulk density of market available sodium percarbonate (SPC) is often no less than 850 kg/m3，it is therefore difficult to blend uniformly between the detergent and the SPC due to their difference in bulk density. The method and techniques for synthesizing low-density SPC by the wet-method were proposed. The factors，such as stabilizer and process conditions affecting the stability and density were examined. The stability mechanism of external stabilizers，such as magnesium sulfate was discussed. The bulk density of this newly prepared SPC varied from 550 kg/m3 to 750kg/m3，the wet stability was larger than 60%，and the thermal stability was larger than 90%. The average particle size of this low-density SPC varied from 0.5mm to1.0mm.