Purpose: This study was performed to evaluate the effect of ZrN coating on shear bond strength between commercially pure titanium and denture base resin. Materials and Methods: ZrN was coated on CP titanium by ion plating method after sandblasting with aluminum oxide. Denture base resin (6mm diameter and 3 mm height) was cured onto CP titanium in both groups (CP titanium and ZrN coated CP titanium). Shear bond strength and surface roughness were measured. The surfaces of the discs were examined by a scanning electron microscope. Results: Shear bond strength in the ZrN coating group (3.79±2.30 kgf, ranged from 1.4 to 7.4 kgf) was significantly lower than that in the non-coating group (9.94±6.08 kgf, ranged from 1.8 to 19.6 kgf) (p<0.05). There was no significant difference between the two groups in surface roughness. Adhesive failure was observed in the ZrN coating group, and mixed failure was observed in the noncoating group. Conclusion: These results suggest that ZrN coating on CP titanium decreases the shear bond strength.