In　terms　of　weighted　scale-free　networks＇　properties,　this　paper　proposes　edges　immunization　based　on　discrete　particle　swarm　optimization　algorithm.　We　translate　the　virus　immunization　problem　to　a　multi-objective　optimization　problem　in　this　paper.　After　a　set　of　edges　are　immunized,　the　network　is　divided　into　sub-networks　whose　nodes　strength　and　average　path　length　are　as　small　as　possible.　Experiment　results　show　that　the　proposed　algorithm　has　a　higher　spread　threshold　and　better　performance　than　the　traditional　immunization　strategies.　©　2012　IEEE.