Polymer-based materials can be made electrically conductive by adding reinforcing particulate conductive material. Instead of using high aspect-ratio conventional fillers, such as fibres and flakes, highly porous silver nanopowders can be used in polymer matrix composites. Such porous morphology contributes to improving electrical conductivity and mechanical properties of nanopowders-polymer matrix composite due to its irregularly shaped surface which prevents or minimises delimitation in the composite structure. In this study, porous nanopowders were produced by the inert gas condensation method with various production parameters such as, different O-2 amount, wire feeding rates, gas types and pressures. Effect of those parameters on the size, morphology and specific surface area of the nanoparticles were determined. (C) 2003 Elsevier B.V. All rights reserved.