The work aims to gather scientific data for industrial production of TiBN coating by preparing TiBN nanocomposite coating at low temperature in pure N2. TiBN coating was deposited on cemented carbide substrates by using ion source-enhanced cathodic arc ion plating system. Effects of N2 pressure on crystal microstructure, morphology, hardness and wear resistance of the TiBN coating were investigated systemically. Facts proved that N2 pressure had obvious effects on crystal microstructure, morphology, hardness and friction coefficient of the coating. As the N2 pressure increased, TiN crystal phases in the TiB2 coating increased while TiB2 crystal phases decreased. The structure of TiBN coating was a composite structure with TiN crystal grains and TiB2 crystal grains embedded in amorphous BN substrate. The microhardness was up to 3150HV at the N2 pressure of 0.5 Pa. For grinding material cemented carbide, The friction coefficient of TiBN coating was nearly 0.4. Ion source-enhanced arc ion plating technology can be used to prepare TiBN coating, a nanocomposite coating of high microhardness with nanocrystalline embedded in amorphous substrate. The pressure of N2 should be low during industrial production of TiBN nanocompisite coating.