Microstructure,　texture　and　mechanical　properties　in　the　weld　joint　of　variable　polarity　plasma　arc　welding　of　5A06　Al　alloy　under　the　condition　of　non-axisymmetric　arc　have　been　investigated.　The　weld　joint　are　characterized　by　elongated　structure　in　the　base　material　(BM),　the　heat　affected　zone　(HAZ)　and　the　transition　zone　(TZ)　and　equiaxed　structure　in　the　fusion　zone　(FZ).　Microstructure　of　the　weld　joint　is　asymmetrical　and　in　homogeneous　leading　to　deformation　bands.　Deformation　texture　and　recrystallization　texture　were　developed　in　the　weld　zones.　The　FZ　center　was　dynamic　recrystallized　due　to　severe　deformation.　Materials　in　the　TZ　have　undergone　dynamic　recovery.　The　weld　zones　are　harder　than　the　BM　due　to　dislocation　sub-structure,　deformation　bands　and　ultrafine　subgrains.　Microhardness　distribution　was　homogeneous　in　the　regions　without　deformation　bands.　Tensile　fracture　occurred　along　the　deformation　bands　on　the　side　of　＂lower　arc＂　exhibiting　ductile　fracture,　while　the　BM　is　less　ductile.