Little work has been reported directly compared to the tribological behavior of plasma nitrided pure titanium and those coated with TiN coatings. This work prepared the compound layers and coatings with the same thickness on TA2 pure titanium by plasma nitriding and multi-arc ion plating. The tribological behaviors of sliding against ZrO2 balls under lubricant conditions were investigated using a UMT-5 tribo-tester. The results reveal that nitrided and coating samples showed the friction coefficients (0.11-0.12) were significantly decreased compared to that (~0.33) of the TA2 pure titanium matrix. It was also found that the wear mechanism is different after nitriding or coating, which is caused by the surface phases, chemical composition, and surface roughness under other processes.