The invention discloses a composite sound absorbing and insulating board. The composite sound absorbing and insulating board has a multi-layer structure, wherein an air layer is arranged between two panel honeycomb sandwich layers, so that the respective obstructing wave troughs can be avoided, the integral sound insulation property of the board can be effectively improved, meanwhile, elastic damping layers are arranged between a fireproof layer and a sound absorption layer and between the sound absorption layer and a sound insulation layer, so that the sound insulation amount and sound insulation frequency can be further improved, the propagation of noise can be effectively obstructed, and the composite sound absorbing and insulating board has the advantages of large sound insulation amount, wide sound insulation frequency and good sound absorbing and insulating properties. Due to the adoption of the structural form that the air layer is arranged between the two panel honeycomb sandwich layers, the composite sound absorbing and insulating board also has the features that the strength is high, the weight is small, meanwhile, the weather resistance, the fireproofing property and the like are also excellent, and the composite sound absorbing and insulating board is suitable for vibration and noise reduction in various fields including buildings, ships, automobiles and the like, and is wide in application range.