The electrical conductivity, band gap, dielectric permittivity, and molar polarizability of Zn2(Ti aSn b)1 − xZr xO4 solid solutions have been determined. All of the synthesized samples are dielectrics with semiconducting behavior of conductivity. The phase diagram of the Zn2TiO4-Zn2SnO4-Zn2ZrO4 system is presented.