Based　on　the　hypothesis　of　periodically　well-distributed　microstructure　of　carbon　black　filled　rubber　composites,　three-dimensional　representative　volume　elements　(RVE)　with　multi-sphere　particles　randomly　distributed　have　been　generated　using　a　new　modified　Random　Sequential　Adsorption　algorithm,　and　the　macroscopic　mechanical　properties　of　the　carbon　black　filled　rubber　composites　have　been　studied　and　analyzed　by　the　microscopic　finite　element　method.　The　results　show　that　the　models　generated　by　the　modified　Random　Sequential　Adsorption　algorithm　are　more　suitable　for　finite　element　discretization　and　the　simulations　can　describe　the　reality　better　by　the　periodic　boundary　conditions.　It＇s　also　shown　that　the　modulus　of　the　rubber　composite　is　increased　considerably　with　the　introduction　of　carbon　black　filler　particles,　and　the　effective　elastic　modulus　of　the　rubber　composite　is　increased　with　the　increase　of　the　particle　volume　fraction.　By　comparison,　it　is　shown　that　the　results　predicted　by　the　present　method　are　consistent　well　with　the　experimental　results,　demonstrating　that　this　model　can　be　used　for　simulation　analysis　of　effective　properties　of　the　carbon　black　filler　particle　reinforced　rubber　matrix　composites.