Abstract: In order to study the sound insulation of glass fabric/PVC composite material and improve its property,the glass fabric/PVC composites were manufactured from glass fibers with different diameters and PVC resin with high damp.The two-channel acoustic analyzer,SEM,etc were used to analyze the sound insulation property and micro-structure of the samples.The results showed that glass fiber′s fineness has great influence on the sound insulation property of both fabric and composite material.With the same density and thickness,the finer the glass fiber,the better the sound insulation of the fabric and composite material.