Here, we report the preparation of nano silver (Ag) and nano Ag-erbium (Ag-Er) co-embedded potassium-zinc-silicate based monolithic glass nanocomposites by a controlled heat-treatment process of precursor glasses. The nanocomposites were characterized by differential scanning calorimeter, dilatometer, UV-Visible absorption spectrophotometer, X-ray diffractometer and transmission electron microscope and spectroflurimeter. A strong surface plasmon resonance (SPR) band is observed around 430 nm in all the heat-treated glass nanocomposite samples due to the formation of Ag0 nanoparticles (NP). The Ag-glass nanocomposite samples display nearly 2-fold enhanced photoluminescence (PL) at 470 nm upon excitation at 290 nm until the size of the NP increases to the value equals to the mean free path of conduction electrons inside the particles. On contrary to this, the photoluminescence spectra of Er3+ ions exhibit a gradual decrease of NIR emission at 1540 nm due to 4I13/2 †' 4I15/2 transition under excitation at 523 nm in the heat-treated glass nanocomposites which happened due to excitation energy transfer of Er3+ ions to the Ag NP, acting as 'plasmonics diluents' for Er3+ ions. These nanocomposites have huge potential for various nanophotonic applications. © 2014 Elsevier Masson SAS.