A　generalized　molecular　structure　mechanics　(MSM)　model　is　proposed　to　investigate　the　deformation　and　failure　behaviors　of　super　carbon　nanotubes　(SCNTs)　within　the　quasi-static　approximation.　The　failure　mechanism　of　the　SCNTs　with　Y-　and　X-type　junctions　was　examined　by　combining　a　failure　criterion　for　the　breakage　of　the　carbon-carbon　bonds　in　the　CNT　networks.　The　carbon-carbon　bonds　are　modeled　as　elastic　bars　with　equivalent　stiffness　and　break　as　their　elongation　ratio　reaches　only　19%,　which　means　that　the　broken　carbon-carbon　bonds　are　ineffective　in　terms　of　the　Morse　potential　function.　It　is　shown　that　the　MSM　method,　combined　with　the　failure　criterion　of　the　carbon-carbon　bonds,　is　a　powerful　approach　to　simulate　the　deformation　and　failure　of　both　Y　junctions　and　X　junctions　with　different　chiralities　and　sizes.　The　deformation　and　failure　modes　of　these　junctions　which　involve　rotation,　bending　and　stretching　of　the　CNT　arms　are　predicted　using　the　present　model　and　the　effects　of　various　parameters　of　the　junctions　on　their　mechanical　behaviors　are　discussed.