Polycrystalline-sintered samples of Ag 8 GeTe 6 were prepared and the electrical resistivity and Seebeck coefficient were measured from room temperature to about 800K. The sample density is about 89% of the theoretical density. The electrical resistivity at room temperature is 1.87×10 −3 Ωm, which is about 100 times higher than that of Bi 2 Te 3 . The Seebeck coefficient is negative in the whole temperature range, showing that the majority of charge carriers are electrons. The value at room temperature is −123μVK −1 . The thermal conductivity was measured only at 770K. The value is 0.3Wm −1 K −1 , which is about one-third of that of Bi 2 Te 3 .