Substitution of lithium for silver in silver antimonate was done up to 0.16 lithium by soft chemistry or solid state chemistry. The variation of the conduction was followed by impedance (AC) and resistance (DC) measurements up to 750 K. Below 580 K, the conduction of the silver antimonate is dominated by electronic conduction and above, ionic conduction due to silver hopping across the vacancies of the pyrochlore structure is observed. In the substituted compounds, the electronic conductivity decreases when the level of lithium increases and ionic conductivity due to lithium is superimposed up to 580 K. Above, a conduction process by polaron including both silver and lithium is proposed.