The polyphosphate glasses with the general formulae LiMII 2(PO3)5 (M=Cu, Zn, Cd, Ba, Pb) were prepared by using the melt-quench technique. They are characterized by X-ray diffraction (XRD), density measurements and differential thermal analysis (DTA). The results show that the glass transition temperature and molar volume increase nonlinearly with increasing of the bivalent cation atomic weight in the sequence Cu<Zn<Cd<Pb<Ba. Measurements of the ionic conductivity were made in the frequency range of 20 - 106 Hz and the temperature range 25 - 300°C. It is found that the Conductivity of the LiZn2(PO3)5 and LiCu2(PO3)5 glasses are much lower than those of the other samples. The differences in conduction properties are discussed based on the structural and atomic properties of the glass components.