In　the　field　of　rock　mechanics,　the　study　of　void　shape　on　the　mechanical　properties　and　fracture　mechanisms　of　sandstone　is　crucial　for　the　progression　of　rock　engineering　practices.　In　this　study,　PFC3D　is　utilized　to　conduct　numerical　simulations　of　uniaxial　compression　on　intact　rock　and　brittle　rocks　containing　five　different　shapes　of　voids　(including　circular,　inverted　U-shaped,　trapezoidal,　rectangular,　and　square).　By　employing　acoustic　emission　and　moment　tensor　inversion　techniques,　the　microscopic　fracture　mechanisms　of　rocks　with　different　void　shapes　are　revealed.　Our　key　findings　reveal:　(1)　The　PFC3D＇s　Soft-Bond　Model　is　adept　at　simulating　acoustic　emissions　with　high　accuracy,　facilitating　an　authentic　reproduction　of　the　uniaxial　compression　process　in　sandstone,　including　the　nonlinear　compaction　stage.　(2)　The　presence　of　hole　defects　markedly　undermines　the　structural　strength　and　deformability　of　the　sandstone,　with　circular　holes　having　minimal　impact,　whereas　rectangular　holes　exert　the　most　significant　detriment.　(3)　A　thorough　analysis　of　fracture　mechanisms　demonstrates　that　specimens　with　hole　defects　primarily　undergo　initial　tensile,　remote　cracks,　V-shaped　notch,　and　shear　fractures,　with　shear　fractures　being　pivotal　in　leading　to　specimen　failure　by　rapidly　evolving　into　macroscopic　fractures　that　merge　with　V-shaped　notches.　(4)　Acoustic　Emission　(AE)　analysis　highlights　the　distribution　of　tensile　stress　around　the　upper　and　lower　extremities　of　the　holes　and　shear　stress　along　the　left　and　right　sidewalls,　establishing　shear　stress　as　the　dominant　factor　in　the　failure　of　specimens　with　hole　defects.