Fracture　and　fragmentation　of　rock　under　various　loadings　or　in　multi-field　conditions　are　important　topics　in　many　rock　engineering　scenarios.　Numerical　tools　are　commonly　applied　to　evaluate　the　rock　deformation　and　progressive　failure　process,　while　the　accuracy　and　efficiency　of　the　analysis　are　closely　related　to　the　applied　fracture　models.　In　this　paper,　an　improved　discontinuous　deformation　analysis　(DDA)　program　with　the　distributed　bond　(DB)　is　proposed　for　rock　deformation　and　rock　fragmentation　analysis.　The　jointed　rock　model　is　regarded　as　an　assembly　of　triangular　elements　connected　with　DBs　and　contacts.　The　DB　uses　distributed　constraints　to　bond　the　co-edge　elements　for　continuous　deformation　modeling,　and　the　fracturing　and　fragmentation　of　rock　material　is　fulfilled　by　progressive　DB　failure　with　linear　and　nonlinear　bond　constitutive　models.　The　theory,　formulation,　and　implementation　of　DB　in　DDA　framework　are　given　in　detail.　The　feasibility　and　accuracy　of　the　proposed　DB　in　simulating　rock　deformation　and　failure　process　are　verified　by　several　examples.