In　heavy　duty　machine　tools,　hydrostatic　turntable　is　often　used　as　a　means　for　providing　rotational　motion　and　supporting　workpiece,　so　the　accuracy　of　turntable　is　crucial　for　part　machining.　In　order　to　analyze　the　influence　of　load-indcued　errors　on　machining　accuracy,　an　identification　model　of　load-induced　errors　based　on　the　deformation　caused　by　applied　load　of　hydrostatic　turntable　of　computerized　numerical　control　(CNC)　gantry　milling　heavy　machine　is　proposed.　Based　on　multi-body　system　theory　and　screw　theory,　the　space　machining　accuracy　model　of　heavy　duty　machine　tool　is　established　with　consideration　of　identified　load-induced　errors.　And　then,　the　influence　of　load-induced　errors　on　space　machining　accuracy　and　the　roundness　error　of　a　milled　hole　is　analyzed.　The　analysis　results　show　that　load-induced　errors　have　a　big　influence　on　the　roundness　error　of　machined　hole,　especially　when　the　center　of　the　milled　hole　is　far　from　that　of　hydrostatic　turntable.