Oxidation　of　the　Ti6Al4V　alloy　at　high　temperature　is　a　problem　for　the　sound　products.　In　order　to　protect　the　alloy　from　oxidation,　surface　coating　method　has　been　attempted　and　several　coating　materials　have　been　investigated.　A　zirconia　coating　is　applied　to　the　surface　of　Ti6Al4V　alloy　by　plasma　spray　and　the　effect　of　coating　on　the　superplasticity　of　the　alloy　as　well　as　the　oxidation　behavior　of　the　oxidation　are　studied.　Uniaxial　tensile　tests　are　conducted　at　800°C,　850°C　and　900°C　with　an　initial　strain　rate　of　0.0001　s-1,　0.001　s-1,　0.01　s-1　and　0.1　s-1.　Studies　show　that　an　oxide　film　is　formed　on　the　surface　of　Ti6Al4V　alloy　and　no　such　oxide　film　is　found　in　the　coated　specimens.　XRD　and　EDX　analysis　indicate　that　this　oxide　film　mainly　consists　of　TiO2.　The　thickness　of　the　oxide　film　increases　with　increasing　temperature　and　exposure　time.　Studies　show　that　the　elongations　of　the　coated　specimens　are　higher　than　those　of　the　uncoated　ones,　while　the　ultimate　strength　and　yield　strength　of　the　alloy　are　not　changed.　The　difference　in　elongation　between　the　coated　and　uncoated　specimens　is　influenced　by　the　temperature　and　initial　strain　rate.　However,　studies　also　show　that　there　are　some　clefts　formed　on　the　coating　layers　at　the　later　stage　of　deformation　due　to　the　brittle　nature　of　the　coating　layers.