A series of different volume-weights of Silicate-based porous sound-absorbing materials, which are cured by different methods or contain different contents of viscosity-controlling agent, have been manufactured by the Portland cement, with the way of in-situ assembly. The sound-absorbing characteristics are tested by the devices of standing wave, the compressive strength of materials is tested by WDW microcomputer servo tensile (compression) testing machine,. The result shows that, Average absorption coefficient of porous sound-absorbing materials is more than 0.7 from 800Hz to 6300Hz. As the increasing of volume-weights and viscosity-controlling agent contents, porous sound-absorbing materials' compressive strength separately increase and decrease. At the same time, different methods of cure and water-cement ratio have significantly effects on high volume-weight porous sound-absorbing materials' compressive strength.