The　Zr-1Nb　alloy　was　treated　by　laser　melting　and　vacuum　annealing　in　order　to　improve　the　high　temperature　corrosion　resistance.　The　morphology　of　the　melting　layer　was　observed　by　scanning　electron　microscopy,　phase　compositions　and　quantities　were　determined　by　X-ray　diffraction　and　Raman;　surface　roughness　was　determined　by　profile　meter;　and　hardness　was　measured　by　the　micro-hardness　tester.　In　order　to　characterize　the　corrosion　resistance,　autoclave　experiments　were　conducted　for　70　days　in　an　aqueous　steam　condition　of　360　under　18.6MPa　in　0.01mol/L　LiOH　solutions.　The　results　show　that　the　surface　roughness　of　Zr-1Nb　cladding　tubes　is　improved　by　laser　melting;　the　laser　melted　layer　is　mainly　composed　of　α-Zr　phase　and　a　small　amount　of　m-ZrO2,　and　the　phase　composition　of　laser　melted　layer　does　not　change　after　heat-treatment;　under　high　power　condition,　laser　melting　can　reduce　the　high　temperature　corrosion　resistance　of　Zr-1Nb　alloy.　However,　the　high　temperature　corrosion　resistance　of　Zr-1Nb　alloy　can　be　improved　significantly　under　the　condition　of　low　power　laser　melting　and　auxiliary　heat　treatment　process.　By　laser　melting　treatment,　microhardness　of　zirconium　alloy　can　be　increased　by　50-80HV0.1.　And　after　heat　treatment,　microhardness　of　zirconium　alloy　is　decreased　compared　with　the　laser　melted　sample,　but　it　is　still　higher　than　the　origin　sample.　©　2018,　Journal　of　Materials　Engineering.　All　right　reserved.