For the concentration dependence of the criterion of light-sound interactionM2 in lead-bismuth-germanate glasses, a regression equation of an incomplete third order is obtained, which approximates the value ofM2 with a relative mean-square error of 4%. Partial coefficients of the oxide components of the glasses are established, which characterize their contribution to the acoustooptical efficiency of the material. The PbO-Bi2O3-GeO2 system can yield glasses withM2 equal to 37×10−15 sec3/kg, which exceeds theM2-values of industrial dense flints by a factor of 5–7. The data obtained can be used for designing new compositions of optical media used for the production of light-sound guides of acoustooptical devices.