The stationary wave tube method was used to measure the sound absorption coefficient of wood wool boards.Effects of thickness,density,back cavity depth and density combination were used to analyze sound absorption performance of the boards.Results showed that the wood wool board conformed to absorption mechanism of porous material as audio frequency ranging from 0 ,2 000Hz.Sound absorption performance was improved as the board density and thickness inceased. And sound absorption coefficient could be improved by deeper cavity on the back side.The wood wool board having 10 mm thickness and 0.50 g/cm3 density was an ideal sound absorption material.Combination of different board densities could improve acoustic performance.