The　microstructures　and　tensile　properties　of　electrodeposited　nanocrystalline　Ni　(nc-Ni)　with　a　broad　grain　size　distribution　after　annealing　at　150,　200　and　300°C　for　500　s　were　investigated.　The　as　deposited　broad　grain　size　distribution　nc-Ni　sample　exhibited　a　moderate　strength　σUTS　of~1107　MPa　but　a　markedly　enhanced　ductility　σTEF　ofy10%,　compared　with　electrodeposited　nc-Ni　with　a　narrow　grain　size　distribution.　Annealing　below　200°C　increased　the　strength　but　caused　a　considerably　reduction　in　tensile　elongation.　This　behaviour　is　attributed　to　the　grain　boundary　relaxation　and　the　increased　order　of　grain　boundaries　after　annealing,　which　can　make　the　grain　boundary　activities,　such　as　the　grain　boundary　sliding　and　grain　rotations,　more　difficult.　Further　annealing　at　300°C　decreased　both　the　yield　strength　and　tensile　elongation　significantly　due　to　significant　grain　growth.　©　2011　Institute　of　Materials,　Minerals　and　Mining.