By　introducing　a　time　relaxation　term　for　the　time　derivative　of　higher　frequency　components,　we　proposed　a　stabilized　semi-implicit　Galerkin　scheme　for　evolutionary　Navier-Stokes　equations　in　this　paper.　Analysis　shows　that　such　a　scheme　has　weaker　stability　conditions　than　that　of　a　classical　semi-implicit　Galerkin　scheme　and,　when　a　suitable　relaxation　parameter　sigma　is　chosen,　it　generates　an　approximate　solution　with　the　same　accuracy　as　the　classical　one.　That　means　the　proposed　scheme　might　use　a　larger　time　step　to　generate　a　bounded　approximate　solution.　Thus　it　is　more　suitable　for　long　time　simulations.　(C)　2009　Elsevier　B.V.　All　rights　reserved.