The　kinematics　and　dynamics　of　free-floating　space　robot　system　with　dual-arms　were　analyzed,　and　it　is　shown　that　the　Jacobian　matrix　and　the　dynamics　equations　of　the　system　are　nonlinearly　dependent　on　inertial　parameters.　In　order　to　overcome　this　problem,　the　system　was　modeled　as　under-actuated　robot　system,　and　the　idea　of　augmentation　approach　was　adopted.　It　is　demonstrated　that　the　dynamics　equations　of　the　system　can　be　linearly　dependent　on　a　group　of　inertial　parameters.　Based　on　these　results,　a　robust　variable　structure　control　scheme　for　spacecraft-referenced　end-point　motion　of　free-floating　space　robot　system　with　dual-arms　with　uncertain　inertial　parameters　was　proposed,　and　a　planar　space　robot　system　with　dual　arms　was　simulated　to　verify　the　proposed　control　scheme.　The　advantage　of　the　scheme　is　that　it　requires　neither　measuring　the　position,　velocity　and　acceleration　of　the　floating　base　with　respect　to　the　orbit　nor　controlling　the　position　and　attitude　angle　of　the　floating　base.　In　addition　to　this　advantage,　it　is　computationally　simpler　by　choosing　to　make　the　controller　robust　to　the　uncertain　inertial　parameters　rather　than　explicitly　estimating　them　online.