Geothermal　mining,　nuclear　waste　disposal,　and　other　projects　involve　rock　fracturing　under　the　multiphysics　effect.　There　is　an　urgent　need　for　a　numerical　analysis　tool　that　can　consider　both　thermal-hydro-mechanical　coupling　(THM)　effects　and　rock　fracturing　to　analyze　such　projects.　This　paper　presents　a　three-dimensional　thermal-hydro-mechanical　coupling　model　that　can　consider　rock　fracturing,　which　incorporates　the　advan-tages　of　the　combined　finite　discrete　element　method　(FDEM)　for　simulating　fracture　and　fragmentation.　The　3D　thermal-hydro-mechanical　coupling　model　includes　three　parts:　fracture-pore　mixed　seepage　model,　heat　transfer　model　(including　heat　conduction　in　solid　and　fluid,　heat　advection,　heat　exchange　between　solid　and　fluid),　and　FDEM　fracture　mechanics　calculation　model.　Some　examples　with　the　analytical　solution　for　seepage,　hydromechanical,　thermal-mechanical,　hydrothermal,　and　thermal-hydro-mechanical　coupling　problems　are　used　to　verify　the　correctness　of　the　FDEM　based　3D　THM　model　in　detail.　In　addition,　an　example　of　rock　fracturing　caused　by　the　thermal-hydro-mechanical　coupling　effect　is　also　given.　The　simulation　results　show　that　the　FDEM　based　3D　thermal-hydro-mechanical　coupling　model　can　simulate　the　complex　fractures　initiation,　propagation,　and　extension　caused　by　multiphysics　effects,　such　as　heat,　fluid,　and　mechanics.