A laminated plyboard for a musical instrument which reduces a loss of vibration energy due to internal friction while securing high rigidity with inexpensive cost. A laminated plyboard 20 comprises a first layer portion S1 including layers 24 and 25, a second layer portion S2 including layers 26 and 27, and an impregnated layer 21 impregnated with phenol and sandwiched between the first layer portion S1 and the second layer portion S2. A rigidity coefficient of the impregnated layer 21 is higher than rigidity coefficients of the layers 24 to 27 that configure the first layer portion S1 and the second layer portion S2.