Thermoelectric power studies on Ag7I4VO4. superionic conductor have been carried out in the temperature range 25 to 60°C. Thermo-electric power is found to vary linearly with the inverse of the absolute temperature, and can be expressed by the equation -θ = [(0.182 × 103/T) + 0.276] mV/K. The heat of transport is nearly equal to the activation energy of Ag+ ion migration calculated from the conductivity plots indicating that the material has an average structure. © 1986.