The polyvinyl alcohol (PVA)-colloidal silver (Ag) nanocomposites were prepared mixing the colloidal Ag with PVA water solution, in presence of poly(diethylene adipate lactate) diol (PDEAL), The effect of very low amounts of colloidal Ag (below 50 ppm) on the PVA matrix was investigated. The neat PVA sample and PVA-colloidal Ag nanocomposites were characterized using transmission electron microscopy (TEM), scanning electron microscopy (SEM), differential scanning calorimetry (DSC) and as physico-mechanical behaviour. Both TEM and SEM techniques showed that the colloidal Ag was present inside of the PVA matrix as spherical particles in the nanometer dimensions, and as clusters. Mechanical analysis via stress-strain testing, as well as the dynamic mechanical analysis (DMA) showed a substantial increase of the mechanical properties of the nanocomposite materials, against those determined for the PVA matrix.