Vacuum ultraviolet (VUV) is profitable to strengthen the efficiencies of UV and reduce chemicals use, attracting more attention to water and wastewater purification. Herein, VUV-based water treatment processes from unitary VUV to multicomponent systems were reviewed for the first time to promote VUV applications. The rate of pollutant removal by unitary VUV was 1.3-57 times that of UV, in which hydroxyl radical oxidation was dominant. And the reducibility of hydrated electron and hydrogen atom radical in unitary VUV dehalogenated organics and reduced metal ions. Besides, VUV-based binary systems mainly included processes of VUV/H