The　thermophysical　properties　of　thermal　equilibrium　and　non-equilibrium　nitrogen　plasmas　at　high　temperatures　are　presented　in　this　paper.　The　cut-off　of　partition　functions　due　to　the　lowering　of　the　species　ionization　potential　and　contributions　corresponding　to　the　different　electronic　cores　have　been　considered.　The　species　composition　and　thermodynamic　properties　are　determined　by　numerical　codes　of　Newton-Raphson　iteration,　considering　the　Debye　correction.　The　transport　properties　are　evaluated　with　accurate　collision　interaction　potentials　by　performing　Devoto＇s　electron　and　heavy　particles　decoupling　approach　expanded　up　to　the　third-order　approximation　(second-order　for　viscosity).　The　results　are　compared　with　available　results　of　previously　published　studies　and　the　influences　of　different　definitions　of　the　Debye　length　on　the　properties　are　discussed.