Three　silver　nanoparticles　of　different　size　characterized　by　the　UV-vis　absorbance　spectra　and　TEM　images　were　prepared　by　citrate　reduction　and　laser　ablation　with　excitation　of　532　and　248　nm.　It　is　proved　that　all　of　them　are　effective　SERS-active　substrates,　whereas,　enhancement　effect　of　silver　colloids　has　not　too　much　relation　with　the　size　and　shape　of　the　Ag　nanoparticles.　However,　different　photoluminescence　spectra　were　observed　from　these　three　particles,　indicating　that　the　photoluminescence　property　of　silver　nanoparticles　is　dependent　on　the　size.　The　spectra　shift　to　higher　energies　with　decreasing　particle　size.　In　addition,　we　also　tentatively　give　the　assignment　of　the　luminescence　bands.　(c)　2006　Elsevier　B.V.　All　rights　reserved.