The effect of the different cations Mg2+, Cd2+, Zn2!, Ca2Sr2+, Ba2 + AF+, Ti4+ and Zr4+ on the frequencies and intensities of the characteristic infrared absorption bands of some selected high lead silicate glasses, was investigated. The raw' materials used were all of chemically pure grade and finely pulverised. The tem¬perature of melting ranged from 1100 to 1200 C, depending on the glass composition. All the ab¬sorption measurements were recorded in the range of 4000-200 cm"1 using URIO fully automa¬tic double beam infrared spectrophotometer. Alkali halide disc technique was used. The effect of these different cations on the deformation of SiO4 tetrahedra was studied, and it has been found that their behaviour depend on the type, coordination number and quan-tity of the cations introduced; and also on the introduction of new structural units.