The　brittle　failure　induced　by　high　in-site　stress　occurring　at　the　tunnel　face　significantly　affect　the　TBM　performance.　To　study　the　rock　mass　failure　mechanism　under　the　combined　effect　of　high　stress　and　TBM　cutters,　three　groups　of　true-triaxial　rockburst　tests　were　conducted,　simulating　the　failure　processes　using　the　loading　scheme　＂one-single　face　free　and　the　remaining　five　surfaces　loaded＂.　Conditioned　granite　specimens　previously　cut　by　the　TBM　cutter　were　prepared,　and　the　different　stressed　conditions　were　determined　based　on　the　in-situ　stress　field　of　the　Yinhan　water　conveyance　tunnel.　As　the　confining　stress　increased,　the　peak　strength　of　the　rock　specimen　also　increased,　and　the　final　rupture　was　more　violent,　leading　to　a　rockburst.　The　failure　process　recorded　by　the　high-speed　camera　and　the　failure　pattern　showed　a　clear　change.　The　rock　conditioned　by　the　TBM　cutter　was　more　susceptible　to　brittle　failure　under　high　stress,　and　the　failure　depth　was　greater.　The　stressstrain　curves　in　the　&　sigma;1　direction　and　the　AE　characteristics　indicated　that　as　the　loading　stress　increased,　the　damage　in　the　rock　changed　from　a　dominant　tensile　failure　to　a　dominant　shear　failure,　gradually　extending　to　deeper　areas　of　the　rock.　This　alteration　changed　the　rock　mass　mechanical　behavior　of　the　tunnel　face,　i.e.,　its　stability　and　boreability,　consequently　influencing　the　rock　breakage　process　by　TBM　cutters.　As　the　severity　of　failure　increased,　the　TBM　performance　shifted　from　a　low　efficiency　rock-breaking　performance　limited　by　the　cutter　thrust　to　a　high　efficiency　rock-breaking　performance　limited　by　the　muck　capacity　and　safety　control.