The　first-principles　calculations　were　performed　based　on　density　functional　theory　to　study　the　structural,　electronic　and　magnetic　properties　of　Ni4C　resulting　from　carbon　atom　diffusion　in　a　conventional　Ni　unit　cell.　Firstly,　geometry　optimization　was　performed　to　reach　the　equilibrium　state　of　Ni4C.　The　lattice　constant　of　the　stable　Ni4C　crystal　structure　was　larger　than　that　of　the　Ni　unit　cell.　Then　the　electronic　and　magnetic　properties　of　Ni4C　were　determined,　and　the　results　showed　that　the　magnetic　moment　was　0.46　μB　per　unit　cell,　and　the　calculated　local　magnetic　moment　of　carbon　atoms　was　0.　There　were　two　occupied　sites　for　Ni　atoms　with　different　local　magnetic　moments,　which　was　about　0.64　μB　(close　to　that　of　nickel　unit　cell)　for　Nia　atoms　at　the　top　corners　and　a　negative　value　of　-0.06　μB　for　Nib　atoms　at　the　face　center.　The　magnetic　moment　increased　abruptly　to　1.89　μB　at　3.79　Å　due　to　the　changes　of　lattice　parameters　with　external　factors,　and　fluctuated　slowly　from　3.5　Å　to　3.78Å.　©　2014　The　Authors.　Published　by　Elsevier　B.V.