It is experimentally shown that the electrolysis of silver salt in silicate nanoporous glasses (NPGs) with interconnecting pores, having average sizes of 25 nm, makes possible to fabricate metal-glass nanocomposites. Silver component of nanocomposites consists of fractal microbranches, which, in turn, consist of silver nanowires. By iodizing silver nanowires can be transformed to AgI nanowires. Absorption and luminescence spectra of fabricated nanocomposites are presented. Dielectric spectra of “Ag nanowires-glass” nanocomposite were measured in temperature range of −50 … +250 OC for frequencies of 0.1–106 Hz. Dielectric measurements of “AgI nanowires -glass” nanocomposite have shown the presence of phase transition, typical for crystalline AgI.