The dielectric properties of zinc oxide material are measured at high temperature and in microwave frequency ranges. The real and the imaginary parts of the complex permittivity are calculated using the measured shift on frequency of the full computerized cavity perturbation technique working in microwave frequency ranges, 615 MHz, 1412 MHz, 2214 MHz, 3017 MHz, and 3820 MHz at temperature from 25 oC to 2000 oC in step of 50 oC. The temperature and frequency-dependent electrical conductivity, σ, of zinc oxide is calculated using the complex permittivity imaginary part, ε'', measured in the microwave frequency and the temperature ranges of the above technique. The frequency exponent n, and the activation energy, EA, are determined using the calculated electrical conductivity, σ, in the same microwave frequency and the same temperature ranges.