Ordered　metal　nanoparticle　(NP)　arrays　have　attracted　tremendous　attention　for　potential　plasmonic　applications　due　to　their　unique　surface　plasmon　resonance.　Herein,　we　fabricated　highly　ordered　Ag　NP　arrays　employing　anodized　aluminum　(Al)　templates　and　the　vacuum　thermal　evaporation　technique.　The　morphological　evolution　and　corresponding　optical　property　changes　of　the　Ag　NP　arrays　during　annealing　treatment　has　been　investigated.　It　is　found　that　there　is　a　transition　point　approximately　at　annealing　temperature　of　290　degrees　C,　where　the　shape　of　Ag　NPs　is　most　spherical　and　the　peak　position　of　quadrupole　mode　has　a　largest　wavelength　about　500　nm.　Then,　the　surface-enhanced　Raman　spectra　of　Rhodamine　6G　on　Ag　NP　arrays　annealed　at　different　temperatures　has　been　demonstrated　at　an　excitation　wavelength　of　532　nm.　The　maximum　SERS　enhancement　is　also　observed　at　290　degrees　C.　Our　findings　provide　a　way　to　further　improve　the　performance　of　the　plasmonic　structures.