Zr and Zr-alloys are widely used in biomedical implants, prosthetic components, and dental prostheses due to their high fracture toughness, strength, wear resistance, and good biocompatibility [1] in comparison with other common biomaterials including CoCrMo alloys, Ti-6Al-4 V, and 316L stainless steel [2]. The oxidized zirconium (OxZr) alloy with the trade name OXINIUM utilizes oxidation to transform the metallic surface into a ceramic one. ZrO2 has been used as a coating on metallic substrates to enhance cell adhesion and proliferation while providing abrasion and wear resistance [3,4]. However, in physiological environments, even stable and noble metals can form harmful complexes [5]. This study aimed to enhance the surface corrosion and tribocorrosion in the body simulated condition of Zr-2.5Nb by applying an adherent black-coating of ZrO2 using the thermal heat treatment technique in the air at 523 °C for 3, 4, and 5 h and 700 and 800 °C for 1 h. XRD patterns and Raman spectra revealed that the major components in the black coating are monoclinic and tetragonal ZrO2. Similar results have been reported before showing the major m-ZrO2 phase with trace amounts of t-ZrO2. Cross-sectional images including EDS spectra illustrate the adherent black coatings with thickness of 3.03 to 5.96 µm. The tribocorrosion test is performed at OCP in the phosphate-buffered saline (PBS) solution adjusted to a pH of 7.4 ± 0.1. The tribocorrosion test indicated the lowest volume loss about 0.024 mm3, and showed no potential fall during the sliding test against the SiC ball due to the hardness of coatings. The hardness of the coating might affect the wear resistance, which is controlled by the phase composition and porosity levels. Moreover, the specimen oxidized at 523 °C for 4 h shows the best improvement over the bare substrate in the long-term corrosion performance in the PBS after 16 weeks of immersion. Rout which illustrates the outer porous layer of the ZrO2 coating is only 360 kΩ.cm2 whereas Rin is 98 MΩ.cm2 which indicates the excellent barrier performance of the inner layer.