The　flawless　nanocrystalline　(nc)　Ni　with　a　broad　grain　size　distribution　ranging　from　5　to　120　nm　and　an　average　grain　size　of　20-30　nm　were　prepared　by　direct　current　and　pulse　electrodeposition,　respectively.　In　the　region　of　room-temperature　static　tensile　strain　rates,　for　the　nc　Ni　prepared　by　direct　current　electrodeposition,　the　average　ultimate　tensile　strength　and　the　average　elongation　to　failure　are　1176　MPa　and　10.6%,　respectively.　While　for　the　nc　Ni　prepared　by　pulse　electrodeposition,　the　ultimate　tensile　strength　exceeds　1500　MPa　and　the　max　elongation　to　failure　reaches　13.3%.　In　contrast　to　the　typical　electrodeposited　nc　Ni　with　a　narrow　grain　size　distribution　below　50　nm,　the　ductility　is　increased　by　more　than　100%　for　the　present　nc　Ni　samples.　This　enhancement　can　be　interpreted　by　the　reason　that　dislocations　can　exist　and　multiply　in　the　large　grains　by　the　mechanism　of　Frank-Read　source　in　the　plastic　deformation　process　revealed　by　theoretical　calculation.　Copyright　©　2009,　Northwest　Institute　for　Nonferrous　Metal　Research.　Published　by　Elsevier　BV.　All　rights　reserved.