The solubility of nitrogen in solid niobium was measured in the temperature range 2473 to 2673 K using electromagnetic levitation technique. Nitrogen solution obeyed Sieverts’ law. The standard heat and entropy of solution of nitrogen in niobium were found to be −1.99 × 105 kJ/kg-atom and −52.3 kJ/kg-atom K, respectively. The equilibrium nitrogen solubility in solid niobium could be expressed as: $$ln\left( {\frac{{wt pct \underset{\raise0.3em\hbox{$\smash{\scriptscriptstyle-}$}}{N} }}{{\sqrt {P_{N_2 } } }}} \right) = \frac{{23950}}{T} - 12.0$$ whereP N 2 is in pascals. The terminal solubility of nitrogen in niobium with respect to Nb2N was found to be: $$wt pct \underset{\raise0.3em\hbox{$\smash{\scriptscriptstyle-}$}}{N} = 78.1 exp\left( { - \frac{{9270}}{T}} \right)$$