This study investigates the influence of viscoelastic properties of a series of ethylene-vinyl acetate copolymer on impact noise and vibration damping of wood/polymer/wood sandwich composites. It was found that the impact noise and vibration damping of composites are very sensitive to the state of molecular motion of polymer. The noise and vibration damping of composites was better when the polymer was in the glass transition state (vinyl acetate 55 similar to 75%) at the test-temperature, and it was worse when the polymer was in rubbery state (vinyl acetate 47 similar to 20%) or in glassy state (vinyl acetate 100 similar to 87%). The impact noise decreased by about 6-12dB when the glass transition state of polymer was sandwiched between wood panels.