The　mechanical,　electronic　and　thermal　physical　properties　of　A-type　R2O3　(R=Y,　La)　under　hydrostatic　pressure　are　studied　by　first-principles　calculations.　The　calculated　band　gap　is　6.3　eV　(5.9　eV)　for　Y2O3　(La2O3).　Under　hydrostatic　pressure,　both　phases　show　anisotropic　elasticity　in　different　crystallographic　directions.　The　isothermal　bulk　modulus　of　R2O3　decreases　monotonically　with　the　increasing　of　temperature　from　300　K　to　1500　K.　The　intrinsic　ductile　nature　of　both　phases　is　confirmed　by　the　obtained　B/G　ratio.　The　temperature　dependence　of　linear　TECs　of　La2O3　is　stronger　than　that　of　Y2O3,　and　the　linear　TECs　in　[001]　direction　show　larger　values　in　both　phases　than　those　in　[010]　direction.　At　room　temperature,　the　average　linear　TECs　for　Y2O3　and　La2O3　are　8.40x10(-6)　K-1　and　8.42x10(-6)　K-1,　respectively.　Other　thermal　physical　properties　such　as　specific　heats　(C-V,　and　C-P),　entropy　(S),　sound　velocity　and　Debye　temperature　are　also　obtained.