Ge$_{2}$Sb$_{2}$Te$_{5}$ (GST) has been widely used as a popular phase change material. In this study, we show that it exhibits high Seebeck coefficients 200 - 300 $mu$V/K in its cubic crystalline phase ($it{c}$-GST) at remarkably high $it{p}$-type doping levels of $sim$ 1$times$10$^{19}$ - 6$times$10$^{19}$ cm$^{-3}$ at room temperature. More importantly, at low temperature (T = 200 K), the Seebeck coefficient was found to exceed 200 $mu$V/K for a doping range 1$times$10$^{19}$ - 3.5$times$10$^{19}$ cm$^{-3}$. Given that the lattice thermal conductivity in this phase has already been measured to be extremely low ($sim$ 0.7 W/m-K at 300 K),citep{r51} our results suggest the possibility of using $it{c}$-GST as a low-temperature thermoelectric material.
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