Constrained layer dampers (CLD) are in widespread use for passive vibration damping, in applications including aerospace structures. However, the introducing of the damping layer can reduce the stiffness of the sandwich structures. A viscoelastic material filling (VMF) is chosen to balance structural and vibrational performance of lattice truss in this work. The recently brought forward 3D Kagome truss with face sheet was manufactured by selective laser sintering technology and the thermosetting polyurethane was chosen as the viscoelastic filling material. A novel complex modal analysis finite element method for Hybrid composite lattice truss sandwich is introduced in this paper. Dynamic analysis experiment results show that the VMF method is found to be effective in reducing the vibration amplitude and it has the potential for band-gap design. The VMF method can provide high stiffness at low mass and considerable vibrational performance at low cost and it can be considered as a general vibration design method in lattice truss manufacture.