Nonwoven fabrics which have three dimensional microporous structure have been widely used for noise control in the civil and architecture fields. In this study, the sound absorption properties of the nonwoven fabrics produced by different manufacturing conditions were investigated using an impedance tube method. For the purpose of substitution of conventionally used sound absorber materials with polyester nonwovens, a theoretical model based on the microporous structure of nonwovens was established to predict the sound absorption coefficient(NAC) of nonwoven materials. In conclusion, it was found that the NAC significantly depended on the fiber fineness, web orientation and nonwoven thickness. The nonwovens composed of fine fiber, randomly oriented web and which have higher thickness showed definitely higher NAC than those of the opposite cases. Furthermore, the theoretical model established for the NAC of nonwovens was in good agreement with the experimental results, especially in the high frequency region.