Ionic conductivity and silver diffusion in the Ag₈HgS₂I₆ and Ag₆I₄WO₄ superionic conductors have been studied. The obtained diffusion coefficients of the silver ions are in equations: Ag₈HgS₂I₆ (100-260°C) D^*=2.3×10^-4 exp(-0.128 eV/kT), Ag₆I₄WO₄ (100-200°C) D^* = 6.0×10^-4 exp (-0.183 eV/kT). The calculated values of Haven ratio confirm the existence of essential differences in transfer properties for the solid electrolytes with α-AgI-type structure.