The piezo-optical coefficients ${\mathrm{\ensuremath{\pi}}}_{11\mathrm{\ensuremath{-}}}$${\mathrm{\ensuremath{\pi}}}_{12}$ and ${\mathrm{\ensuremath{\pi}}}_{44}$ of cubic yttria-stabilized zirconia are measured as a function of wavelength, temperature, and yttria concentration. The results show that the piezo-optical coefficients increase nonlinearly with temperature. The dispersion of the elasto-optical constants ${\mathit{n}}^{4}$${\mathit{p}}_{\mathit{i}\mathit{j}}$ for 20-wt % yttria composition is determined and attributed to a direct energy-gap electronic transition.