W-Cu　composite　materials　have　been　widely　used　in　heat　sink　apparatus　and　as　electronic　packaging　materials.　The　preparation　of　the　materials,　especially　the　synthesis　of　W-Cu　nanopowder,　is　a　subject　much　more　researches　on.　This　paper　focuses　on　the　synthesis　of　W-Cu　composite　nanopowder　using　the　freeze-drying　technique,　an　environment-friendly　and　advanced　technique　for　powder　manufacturing.　The　process　involved　mixing　ammonium　metatungstate　with　CuSO4　center　dot　5H(2)O　as　preliminary　liquid　solution　and　the　use　of　liquid　nitrogen　as　a　cryogenic　media;　W-5Cu,　W-10Cu　and　W-20Cu　composite　nanopowders　were　obtained　after　vacuum　drying　and　following　thermal　decomposition　reduction.　X-ray　diffraction,　infrared　spectroscopy　and　field　emission　scanning　electron　microscopy　were　used　to　characterize　these　nanopowders.　The　results　showed　that　the　freeze-drying　precursor　was　the　amorphous　matter　containing　tungstate,　sulfate,　crystal　water　and　ammonia.　Copper　appeared　at　200　degrees　C,　tungsten　and　P-tungsten　could　not　be　obtained　until　500　degrees　C,　and　pure　tungsten　was　found　above　700　degrees　C,　which　meant　that　the　whole　reduction　process　was　completed.　Crystallized　W-Cu　composite　nanopowder,　with　particle　sizes　of　10-20　nm,　was　produced　via　a　two-stage　reduction:　400　degrees　C　for　2　h　and　then　700　degrees　C　for　2　h.　(c)　2009　Elsevier　Ltd.　All　rights　reserved.