To provide a sound absorber which can be constructed lighter in the weight and whose surface has the requisite functions such as fire retardancy, heat resistance, etc.

A porous material 4 and a sound shutoff material 6 are provided on the front and rear surfaces of a resonance structure 3 configured with a plurality of sound absorbing spaces in communication to the front surface side 1, wherein the porous material 4 has a communication hole to receive sonic waves toward the resonance structure 3 while the sound shutoff material 6 hinders the sound having passed the porous material 4 and resonance structure 3 from dispersing to the rear surface side 5. The porous material 4 is made of paper and impregnated with a liquid agent to give the requisite functions.