The surface phonon modes of double-layer dielectric systems of ZnSe Glass and ZnSe/GaAs were observed experimently and calculated by means of boundary condition of polarization field. For ZnSe/Glass

the calculation shows that there are two surface phonon modes

whose positions lie between the TO and LO phonons of ZnSe

varying with the thickness of ZnSe film and the dielectric constant outside ZnSe film. The experimental results are in good agreement with those calculated. For ZnSe/GaAs

among the three calculated surface phonon modes

two modes were observed in experiment

whose Raman shifts are also accordant with the theoretical values. The third surface phonon mode predicted by the calculation did not appear in the measured spectrum

and we think that its position is too close to the TO pbonon of ZnSe to be detected.