The major phase of as-sintered p-type Na(Co 0.95 Ni 0.05 ) 2 O 4 was a solid solution of the constituent oxides, along with a small amount of NaNiO 2 . As-sintered n-type Zn 0.99 Sn 0.01 O was composed of a solid solution of Zn 1−x Sn x O, along with a small amount of Zn 2 SnO 4 . Single π-shaped thermoelectric modules based on p-type Na(Co 0.95 Ni 0.05 ) 2 O 4 and n-type Zn 0.99 Sn 0.01 O were assembled and their thermoelectric properties were studied. The output voltage of the thermoelectric modules enhanced linearly with hot-side temperature (T H ), while the output current exponentially increased with T H . The output voltage and current at T H =650°C were 141mV and 0.768mA, respectively. The maximum output power was calculated by the measured output current and voltage. The higher value of the maximum output power could certainly be obtained with higher hot-side temperature T H . The maximum output power generated from the modules at T H =650°C was as high as 27μW. We believe that the modules are useful for thermoelectric energy conversion at high temperature.