As-annealed　commercial　pure　titanium　was　selected　as　a　model　material　with　hexagonal　close-packed　(hcp)　crystalline　structure.　Dislocation　boundaries　with　different　spacing　values　were　prepared　by　cold　rolling　at　various　reductions.　The　influence　mechanism　of　the　initial　dislocation　boundaries　on　the　adiabatic　shear　sensitivity　of　commercial　pure　titanium　was　investigated　from　two　aspects:　related　dynamic　mechanical　response　and　dislocation　boundary　configuration.　The　geometrically　necessary　dislocation　boundaries　(GNBs)　with　spacing　values　of　550　nm,　340　nm　and　107　nm　were　induced　by　cold　rolling.　The　narrower　the　spacing　of　the　GNBs　was,　the　more　sensitive　the　adiabatic　shearing　behavior　was,　which　was　attributed　to　the　shear　stress　and　adiabatic　temperature　rise.　A　narrow　spacing　of　GNBs　shortened　the　mean　free　path　of　dislocation　slipping;　as　a　result,　the　deformed　resistance　and　accumulated　plastic　deformation　work　became　larger.　Therefore,　the　adiabatic　temperature　rise　that　was　converted　from　plastic　deformation　work　increased,　thereby　strengthening　the　material＇s　adiabatic　shear　sensitivity.　(C)　2016　Elsevier　B.V.　All　rights　reserved.