We successfully synthesized metallic Ni loaded TiO2−x nanoparticles by the solvothermal method. X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and electron paramagnetic resonance (EPR) were used to verify the construction of Ni/TiO2-x heterostructure. The results show that the photocatalytic degradation efficiencies of tetracycline (TC) are greatly improved over the Ni/TiO2-x composites. The optimized Ni/TiO2-x-5% sample displays the best degradation efficiency of 81.5% after 80 min visible light irradiation, much better than that of TiO2 and TiO2-x. Moreover, the Ni/TiO2-x-5% composite can also achieve efficient photodisinfection effects for causative organism including Escherichia coli (E. coli) and Fusarium graminearum (F. graminearum) macroconidia. The boost photocatalytic activities are ascribed to the increased visible light absorption and acceerative separation of photoinduced electron-hole pairs arising from the synergy of oxygen vacancies and Ni nanoparticles. Our work will provide a new strategy of designing non-noble plasmonic photocatalysts for the treatment of environmental remediation.