The　out-of-plane　mechanical　properties　of　aluminium　beams　under　cyclic　bending　were　studied　and　contrasted　to　those　of　steel　beams.　In　order　to　carry　out　research　on　out-of-plane　seismic　stability　performance　of　aluminium　beams,　a　method　by　finite　element　analysis　was　proposed.　The　method　was　based　on　FEA　software,　ANSYS.　The　analysis　methods　considered　the　effects　of　material　nonlinearity,　geometrical　nonlinearity　and　initial　imperfection.　Based　on　above,　hysteretic　curves,　reversal　skeleton　curves　and　stiffness　degradation　curves　of　6061-T6　aluminium　beams,　6061-T4　aluminium　beams　and　Q235　steel　beams　under　cyclic　bending　were　get　and　contrasted.　Results　show　that　the　out-of-plane　seismic　stability　performance　of　the　aluminium　beams　is　lower　than　the　low　carbon　steel　beams　and　is　significantly　influenced　by　material　properties.