In order to improve the adhesion behavior of TiN coatings deposited on H13 steel, a layered composite structure has been developed by plasma nitriding and plasma-enhanced CVD in the present studies. Effects of the nitriding process on the microstructure, adhesion and microhardness, as well as the residual stress of composite nitrided H13 TiN coatings were investigated. Experimental results showed that the adhesion of TiN coatings to substrate could be remarkably enhanced by an optimized plasma nitriding process conducted at a 25% flow ratio of N2 (H2 N2) for 1h. The formation of a new compound layer during a nitriding process at a 50% flow ratio of N2 (H2 N2) deteriorates the adhesion of TiN coatings due to premature brittle fracture between the coating and the substrate. The surface hardness of nitrided H13 TiN coatings and compressive residual stress in the diffusion interlayer increase with increasing pre-nitriding time, but the adhesion of the coatings decreases to some extent.