The　nanocrystalline　nickel　thin　films　with　high　density　nano-scale　growth　twins　were　synthesized　by　means　of　pulse　electrodeposition　technology.　Three　samples　were　deposited　at　different　bath　temperatures　of　30,　50　and　80　degrees　C　by　keeping　all　the　other　parameters　as　constant,　such　as　electrolyte,　pH　value,　current　density　and　on-time　and　off-time　period.　The　effect　of　temperature　on　deposition　rate,　sample　texture,　grain　size,　and　twin　boundary　length　and　twin　lamella　thickness　were　systematically　analyzed　by　SEM,　XRD　and　TEM　techniques.　The　microscopical　feature　of　twin　boundary　were　investigated　by　:HRTEM.　The　results　show　that　the　nano-twinned　nickel　films　deposited　at　the　rates　ranging　from　20　nm/s　to　30　nm/s　have　a　preferred　growth　plane　of　(220)　when　deposited　at　30　and　50　degrees　C　but　changes　to　(200)　when　the　temperature　increases　to　80　degrees　C.　With　increasing　temperature,　the　grain　size　decreases　from　900　to　300　nm,　and　the　twin　lamella　thickness　decreases　from　60　to　28　nm.　The　relationship　between　deposition　temperature　and-nanoindentation　hardness　for　these　films,　moreover　was　determined.　The　nanoindentation　hardness　measurement　indicates　that　the　average　indentation　hardness　of　these　films　reaches　a　maximum　value　of　3.75　GPa　at　50　degrees　C.