More　precisely,　the　electrical　contactor　bounce　should　be　treated　as　a　vibroimpact　problem,　i.e.,　a　strongly　nonlinear　or　catastrophic　one.　The　existing　analytics　is　adopting　the　model　of　rigid　impact　with　a　coefficient　of　restitution,　of　course,　the　model　cannot　give　any　dynamic　information　on　the　contact　force　and　resistance　during　the　contacting　durations.　If　one　intend　to　know　the　information　possible　then　the　contactor　must　be　regarded　as　a　deformable　body.　This　paper　takes　aim　at　that:　1.　linearizing　the　elastoplastic　impact　behavior　of　the　contactors,　2.　suggesting　a　bilinear　vibration　model　of　the　contactor　bounce,　3.　setting　up　a　semi-analytic-numcrical　simulation　method.　From　these　it　is　to　be　got　the　overall　dynamic　information　of　the　contactors　motions,　the　contact　force　and　resistance.　The　results　given　by　the　digital　computer　simulation　show　that　fully　deterministic　as　the　model　is,　in　the　information　there　exist　the　＇chaotic　modulation∗　phenomenon,　similar　to　a　stochastic　proccss,　especially　in　the　resistance　which　had　been　observed　in　a　lot　of　precise　experiments　of　various　electrical　devices　by　several　rescachers.　In　addition,　the　analytics　suggested　here　can　also　be　served　as　a　useful　tool　to　optimize　the　parameters　of　a　electrical　contact　element　for　practical　engineering.　©　1992　IEEE.