Abstract: With the continuous development of nanotechnology, the property of nano-TiO₂ will find ever-increasing wider application, for instance, in the field of pollutant treatment. After a literature review of the current situation in aspects of the mercury-containing wastewater treatment by nano-TiO₂, and analysis is made of its adsorption, the influencing factors in the photocatalytic treatment of Hg(II)and the existing problems in hope of improving the mercury removal efficiency and increasing the use of the adsorption-photocatalytic technology for mercury containing wastewater treatment.