[en] An average figure of merit value of Z∼10^-3/K was achieved for CoSb₃ substituted by Pd (3%) over the wide temperature range 300--800 K. Samples of (Pd_xCo_1-x)Sb₃ compounds, 0< x<0.05, were prepared by hot-pressing the milled powders and by subsequent annealing in inert gas. Measurements of the electrical and thermal transport properties were made on the samples at temperatures ranging from 300 K to 800 K. It was found that the conduction type was n-type and the electron mobility as high as μ_e∼100 cm²/Vs was obtained for a (Pd_0.03Co_0.97)Sb₃ sample. The high value of the mobility can be related to the skutterudite structure that the valence band is only formed by p-p bonds between adjacent Sb-atoms. The doping of Pd into CoSb₃ causes the type conversion from p-type to n-type, and results in a good Seebeck coefficient of S∼-0.3 mV/K, electrical conductivity σ∼3x10² Ω^-1 cm^-1, and low thermal conductivity κ∼0.025 W/cm K at room temperature. copyright 1995 American Institute of Physics