To increase the adhesion strength between the coating and the substrate, sintered Ti(C,N)-based cermets were se- lected and deposited with monolayer TiN using a multiarc ion-plating technique; subsequently, hot isostatic pressing (HIP- ing) treatment was performed at 1000°C using nitrogen pressure up to 110 MPa. The mechanical properties of cermets after a coating process and subsequent HIPing treatment have been evaluated with respect to the hardness, the residual stress, and the coating adhesion. The results show that after the HIPing process, there was a higher increase in critical load in the TiN-coated cermets with lower surface roughness compared with those with higher surface roughness. In all cases, the re- sidual stress was found to be compressive. The effects of substrate surface roughness and posttreatment on the adhesion strength of the coatings were thus investigated. It was also found that the HIPing posttreatment process is well suited for in- creasing the adhesion strength between the coating and the substrate. Following, the hot isostatic pressing (HIP-ing) treatment was performed at 1000 ° C using nitrogen pressure up to 110 MPa. The mechanical properties of cermets after a coating process and subsequent HIPing treatment have been evaluated with respect to the hardness, the residual stress, and the coating adhesion. The results show that after the HIPing process, there was a higher increase in critical load in the TiN-coated cermets with lower surface roughness compared with those with higher with surface roughness. roughness and posttreatment on the adhesion strength of the coatings were thus investigated. It was also found that the HIPing posttreatment process is well suited for in- creasing the adhesion stre ngth between the coating and the substrate.