3D-Kagome　lattice　sandwich　panels　are　mainly　composed　of　upper　and　lower　panels　and　a　series　of　symmetrically　and　periodically　arranged　lattices,　known　for　their　excellent　high　specific　stiffness,　high　specific　strength,　and　energy　absorption　capacity.　The　inherent　geometrical　symmetry　of　the　3D-Kagome　lattice　plays　a　crucial　role　in　achieving　superior　mechanical　stability　and　load　distribution　efficiency.　This　structural　symmetry　enhances　the　uniformity　of　stress　distribution,　making　it　highly　suitable　for　automotive　vibration　suppression,　such　as　battery　protection　for　electric　vehicles.　In　this　study,　a　polyurethane　foam-filled,　symmetry-enhanced　3D-Kagome　sandwich　panel　is　designed　following　an　optimization　of　the　lattice　structure.　A　novel　fabrication　method　combining　precision　wire-cutting,　interlocking　core　assembly,　and　in　situ　foam　filling　is　employed　to　ensure　a　high　degree　of　integration　and　manufacturability　of　the　composite　structure.　Its　mechanical　properties　and　energy　absorption　characteristics　are　systematically　evaluated　through　a　series　of　experimental　tests,　including　quasi-static　compression,　three-point　bending,　and　low-speed　impact.　The　study　analyzes　the　effects　of　core　height　on　the　structural　stiffness,　strength,　and　energy　absorption　capacity　under　varying　loads,　elucidating　the　failure　mechanisms　inherent　to　the　symmetrical　lattice　sandwich　configurations.　The　results　show　that　the　foam-filled　sandwich　panels　exhibit　significant　improvements　in　mechanical　performance　compared　to　the　unfilled　ones.　Specifically,　the　panels　with　core　heights　of　15　mm,　20　mm,　and　25　mm　demonstrate　increases　in　bending　stiffness　of　47.3%,　53.5%,　and　51.3%,　respectively,　along　with　corresponding　increases　in　bending　strength　of　45.5%,　53.1%,　and　50.9%.　The　experimental　findings　provide　a　fundamental　understanding　of　foam-filled　lattice　sandwich　structures,　offering　insights　into　their　structural　optimization　for　lightweight　energy-absorbing　applications.　This　study　establishes　a　foundation　for　the　development　of　advanced　crash-resistant　materials　for　automotive,　aerospace,　and　protective　engineering　applications.　This　work　highlights　the　structural　advantages　and　crashworthiness　potential　of　foam-filled　Kagome　sandwich　panels,　providing　a　promising　foundation　for　their　application　in　electric　vehicle　battery　enclosures,　aerospace　impact　shields,　and　advanced　protective　systems.