The　electrodeposited　nanocrystalline　(nc)　Ni　with　an　average　grain　size　of　27.2　nm　and　with　a　broad　grain　size　distribution　(BGSD)　ranging　from　5　to　120　nm　was　prepared.　The　tensile　strain　rate　(Ε)　jump　test　was　performed　at　room　temperature　to　measure　the　strain　rate　sensitivity　(m).　The　result　shows　that　m　increases　with　decreasing　of　Ε.　In　particular,　when　Ε　is　less　than　2×10-5　s-1,　m　increases　rapidly　which　reaches　0.054　at　Ε=5×10-6　s-1,　indicating　that　the　deformation　mechanisms　involved　in　grain　boundary　diffusion　and　sliding　are　possibly　activated.　The　room　temperature　loading-unloading　tensile　test　was　carried　out.　The　results　show　that　the　capability　of　storing　dislocations　in　BGSD　nc　Ni　is　very　limited　and　the　dislocation　density　is　saturated　when　the　stress　reaches　1052　MPa　with　a　strain　of　7.8%.　From　the　observation　of　TEM　microstructures　in　the　vicinity　of　tensile　fracture,　it　is　confirmed　that　there　is　significant　intragranular　dislocation　sliding　similar　to　that　in　coarse-grained　materials　in　the　process　of　plastic　deformation　of　BGSD　nc　Ni.　©　2010,　Northwest　Institute　for　Nonferrous　Metal　Research.　Published　by　Elsevier　BV.　All　rights　reserved.