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Both p and ntype Si 0.8 Ge 0.2 powders were prepared by gas atomization of a mixture of Si and Ge with the addition of B or P. A part of the gasatomized powders was further pulverized by ballmilling for 10 h in Ar. Then, dense bodies were formed from both the asatomized and pulverized powders by pulsecurrent sinter ing. The thermoelectric properties such as the thermal conductivity, electric resistivity and Seebeck coecient of the dense bodies were determined from room temperature to 1073 K, followed by the evaluation of the gure of merit ( ZT ). The thermal conductivities of p and ntype negrained SiGe from pulverized powders were 8 and 10÷ lower on average in the temperature range of 3001073 K, respectively, than those of the asatomized powders. However, this phenomenon was accompanied with an increase in electric resistivity due to the reduced grain size and increased oxygen content, resulting in the decrease in ZT by 13 and 8÷ for p and ntype SiGe, respectively. The ZT of ntype SiGe exceeded that of ptype because of the high Seebeck coecient of ntype samples. Finally, the largest ZT value of 0.66 was obtained for the SiGe dense body from ntype gasatomized powder. It was found that the application of the gasatomized powder for fabricating SiGe sintered body has the advantage of the reduction in oxygen content and resistivity com pared to the case of the pulverized powders.