Tin　oxide　nanostructured　arrays　with　different　morphologies　were　grown　on　stainless-steel　mesh　substrates　by　a　simple　thermal　evaporation　process.　It　was　found　that　the　SnO2　nanostructures　could　be　easily　changed　from　nanobelts　to　nanocones,　nanoneedles,　micro-rods,　ultra-long　nanowires,　and　slim　nanorods　by　controlling　the　parameters　of　growth　temperature　and　N2/O2　flow.　A　model　combining　vapor-liquid-solid　(VLS)-base　growth　and　vapor-solid　(VS)-tip　growth　was　proposed　to　explain　the　growth　of　SnO2　nanostructures　with　manifold　morphologies.　Field-emission　(FE)　studies　revealed　that　the　morphologies　of　these　patterned　SnO2　nanostructures　had　considerable　effects　on　the　FE　properties.　Among　these　nanostructures,　ultra-long　nanowire　arrays　had　the　lowest　turn-on　field　(~0.47 V/um)　and　the　highest　field　enhancement　factor　(~8848).　More　importantly,　the　ultra-long　nanowire　emitters　showed　excellent　FE　stability　with　fluctuations　within　2.7%.　The　enhanced　FE　properties　may　be　attributed　to　synergic　effects　arising　from　the　aligned　structures　of　the　ultra-long　nanowire　emitters,　their　smaller　areal　density　and　their　highest　aspect　ratio　(~12000).　©　2017　Elsevier　Ltd　and　Techna　Group　S.r.l.