The　three-dimensional　(3D)　negative　Poisson＇s　ratio　auxetic　structures　are　typically　built　based　on　a　series　of　two-dimensional　structures　(2D)　arrayed　in　3D　space　according　to　the　base　vectors.　In　this　paper,　a　unique　lightweight　3D　negative　Poisson＇s　ratio　auxetic　structure　is　proposed　based　on　the　3D　anti-tetra-chiral　structure,　which　can　be　named　as　the　auxetic　contacted　cube　(ACC).　The　internal　struts　of　this　structure　are　connected　using　the　hollow　cubes,　which　reduces　the　stress　concentration　at　the　node　connections　of　the　contacted　struts　by　avoiding　these　connections.　In　addition,　the　structure　possesses　the　identical　periodic　unit-cell　along　all　the　three　orientations　in　the　Cartesian　coordinate,　therefore　it　shows　the　isotropic　mechanical　properties.　The　AlSi10Mg　ACC　specimens　with　different　frame　sizes,　struts　diameters,　number　of　unit-cell,　and　porosity　are　prepared　using　selective　laser　melting　(SLM)　techniques.　Microstructure　analyses　are　conducted　to　prove　the　relative　density　and　formability　of　the　ACC　specimen　satisfying　the　preparation　requirements　of　the　SLM　technology.　The　mechanic＇s　performance　of　27-unit-cells　ACC　structure　with　a　diameter　of　0.5　mm　and　a　porosity　of　89.2　%　is　analyzed　using　the　finite　element　analysis　(FEA)　technology,　indicating　its　negative　Poisson＇s　ratio,　which　is　in　good　agreement　with　the　experimental　results.　The　impact　of　the　building　directions,　the　structural　dimensions,　the　struts　di-ameters,　the　unit-cell　numbers,　and　the　porosity　on　the　mechanical　performance　of　this　ACC　structure　are　sys-tematically　investigated.