Unsupported　Nd-doped　Al2O3　membranes　have　been　prepared　with　a　sol-gel　treatnt　by　using　aluminium　isopropoxide　and　Nd(NO　3)3　as　the　main　raw　materials.　The　properties　of　Nd-doped　Al2O3　membranes　were　characterized　by　XRD,　DTA-TG,　IR　and　N2　adsorption.　The　effects　of　Nd-doping　on　the　phase　composition,　thermal　stability　as　well　as　applications　of　pore-structure　of　Nd-doped　Al　2O3　membranes　at　high　temperature　were　discussed.　The　results　show　that　Nd-doping　can　raise　the　transition　temperature　rom　γ-Al2O3　to　α-Al2O3,　enhance　the　thermal　stability　of　Al2O3　membranes,　and　evidently　improve　the　pore-structural　parameters　of　Al2O3　membranes　applied　at　higher　temperatures.