Photocatalysis is a green, efficient and clean pollutant degradation technology. In this work, a novel Bi₂WO₆ photocatalytic material with oxygen vacancies was synthesized by a simple solvothermal method using ethylene glycol and ethanol as solvents. Tetracycline, as typical antibiotic organic pollutant, was selected to evaluate the photocatalytic activity of the prepared photocatalyst. The prepared oxygen-deficient Bi₂WO₆ material has good photocatalytic activity under visible light irradiation. The results showed that the oxygen-deficient Bi₂WO₆ was regular microsphere in shape with narrower and more uniform pore size distribution than Bi₂WO₆. Moreover, when visible light irradiation was lasted for 180 min, the degradation rate of tetracycline reached 79.68%, showing a higher degradation rate compared with that of Bi₂WO₆. Furthermore, after four cycles, the degradation rate of tetracycline could still reach 68.64%. This was due to the oxygen vacancies significantly enhanced the photocatalytic activity of Bi₂WO₆. In addition, as shown by the UV–Vis DRS analysis, the presence of oxygen vacancies enhances the utilization of visible light by Bi₂WO₆, and reduces the band gap of Bi₂WO₆. This study will provide an innovative idea for the construction of oxygen-deficient photocatalysts for water treatment.