Abstract: A design scheme to add satellite auxiliary support mechanism was proposed to address the fatigue failure of the satellite rocket separation device under horizontal transportation conditions for the satellite/fairing assembly. A mechanical model for the auxiliary support mechanism was established, and an analytical method was used to calculate its important input indicators. In addition, whether or not the performance of the auxiliary support mechanism meets the application requirements was verified through finite element simulation. The proposed auxiliary support mechanism reflects a whole process method covering design input, modeling, calculation and verification, which may provide a reference for the subsequent horizontal transportation of satellite/fairing assemblies.