Ca1-xRExMnO3 (RE: Nd, Tb, Ho, Yb, Lu, x = 0.1 and 0.2) bulks were prepared by a solid state reaction. They show metallic behavior at temperatures higher than about 400 K and electrical resistivity ρ is lower than 12 mΩ cm at 1000 K in air. Absolute values of Seebeck coefficient S increases with temperature up to 973 K for all samples except Ca0.9Yb0.1MnO3 at 973 K. For Ca 0.9Lu0.1MnO3, S value reaches -130 μV/K at 973 K. Both thermoelectric properties are dominated mainly by crystallographic structure. Power factor PF (=S2/ρ) increases with decreasing cell volume. Thermal conductivity K of Yb- and Lu-substituted samples is as low as 1.5 W/m-K2 and dimension-less figure of merit ZT reaches 0.16 at 973 K for Ca0.8Lu0.2MnO3 in air.