Using a general model for sound reflection from multilayered media, we present in this paper the expressions for sound reflection and transmission coefficients on voidcontaining interface layer in solid and derive the characteristic equation for symmetric and antisymmetric modes of the interface waves along the layer. The method for evaluating the effective elasric moduli of void-containing solid is also introduced. The numerical calculation given in this paper shows the influence of the void volume concentration and layer thickness on the sound reflection coefficients and interface wave velocity, providing a theoretical basis for inverse deduction of the mechanical properties of void-containing layer based on ultrasonic measurements.