The use of parallel spin-polarized DT or D3He fuel increases the fusion cross-section by 50%. By implosion-burn simulation for inertially confined fusion (ICF) pellets of the spin-polarized fuels, we found that the input energy requirement could be reduced by nearly a fact of two. These pellets taken up here include large-high-aspect-ratio DT target proposed in ILE Osaka University and DT ignitor/D3He fuel pellet proposed by our group. We also found that the polarized state could survive during the implosion-burn phase.