Abstract: Metro sound absorbed materials are prepared by the concrete molding method and using light ceramisite as aggregate. The influences of aggregate size and gradation, water-cement ratio, cement and admixture content on the sound absorption characteristics and air-flow resistivity were investigated. The results demonstrate that it is favorable to increase the content of the small size ceramisite, reduce watercement ratio, decrease cement content and add definite admixture (expanded perlite or silica fume). With the increase of air-flow resistance, there is an optimum air-flow resistance 1,475 Pa · S/m3 for the best absorbption characteristic. The composition of specimen with better absorption properties and mechanical strength is 25; cement( mass fraction, the same below), the 75; large size (2.4-4.8 mm) ceramisite, water-cement mass ratio is 0. 3, water reducer 4.2 g, expanded perlite addition by cement mass 5;, silica fume addition by ceramisite mass 12;.