A　systematic　study　using　the　first-principles　method　was　conducted　to　investigate　the　interface　relationship　between　TiC　and　TiN　in　high-titanium　steel,　where　TiC　nucleates　and　grows　with　TiN　as　the　core.　The　results　showed　that　the　energy　of　the　(111)　surface　depends　on　the　type　of　terminal　atoms,　with　the　Ti-terminated　surface　exhibiting　lower　surface　energy　than　the　C(N)-terminated　surface.　In　contrast,　the　energy　of　(100)　and　(110)　surfaces　was　independent　of　the　terminal　atom　type.　The　order　of　surface　energy　determined　to　be　(111)Ti＜(100)＜(110)＜(111)-C(N),　the　work　function　exhibits　the　same　trend,　while　the　stability　is　exactly　the　opposite.　Among　all　interface　structures,　the　interface　structure　with　Ti-C　terminal　atomic　combination　was　identified　as　the　most　stable,　which　can　be　attributed　to　the　formation　of　covalent,　ionic,　and　metallic　bonds　at　the　interface.　The　bonding　strength　primarily　arises　from　the　hybridization　between　Ti-d　orbitals　and　C(N)-p　orbitals.　Within　the　(111)　interface　structures,　metallic　bonds　were　formed　in　the　interface　structure　with　the　Ti-Ti　terminal　atomic　combination,　leading　to　the　lowest　interface　energy　and　making　it　thermodynamically　the　most　stable.　Consequently,　TiC　is　capable　of　heterogeneously　nucleating　on　TiN,　with　the　preferred　nucleation　surface　of　TiN　following　the　order　of　(111)＞(100)＞(110).