To explore the DNA damage effect induced by nano-TiO2 in liver and kidney cells, the anatase TiO2 nanoparticles(20-100nm) were prepared for this experiment. 25 Kunming male mice were exposed to different concentrations of nano-TiO2 (0, 0.1, 0.2, 0.4, 0.8mg·mL^-1)for 5d, and then the single-cell gel electrophoresis was applied to measure the DNA damage. Results demonstrated that with the increase of the nano-TiO2 concentrations, the values of Tail DNA% and Tall Moment of mouse liver and kidney cells were gradually increased. For liver cells...