An　Al2O3　coating　was　prepared　from　aluminum　isopropoxide　as　precursor　on　tungsten　substrate.　The　dependences　of　crystalline　and　phase　in　Al2O3　coating　on　temperature　were　studied.　The　results　show　the　coatings　being　compact,　uniform　and　crack-free　can　be　obtained　by　suitable　experiment.　The　main　phase　of　coating　is　alpha-Al2O3.　Compared　to　the　uncoated　specimens,　the　ones　with　coatings　synthesized　by　sol-gel　process　provide　excellent　oxidation　resistance　at　high　temperature.