Abstract: In recent years, the prefabricated lightweight partition wall has been gradually popularized due to its advantages in site construction and manufacturing cost. And the research on its sound insulation performance has attracted more and more attention. Because the sound insulation performance is affected by many factors, a serious of experiments have been conducted to study and analyze the influences of different materials and structures on the sound insulation performance of prefabricated lightweight partition wall. The results show that the sound insulation performance of the prefabricated lightweight partition wall is greatly affected by the acoustic performance of the wall board material itself, and the resonance frequency mainly appears in 125-250 Hz. By increasing the number of layers of the wall board and hanging or sticking glass fiber & magnesium cement board on both sides of the wall, the sound insulation performance of the wall can be effectively improved at low and middle frequencies. By filling rock wool between the keel and the wall board, the sound insulation performance of the wall in the whole frequency bands can be markedly improved and the influence of low frequency resonance on sound insulation performance can be ameliorated effectively at the same time.