In the past decade, rapid development happened in the field of nanotechnology. Recently, nano-material, especially inorganic hybrid molecule, has become an increasingly hot issue in medicine area for safe drug delivery system. In this paper, nano-layered double hydroxides (nano-LDHs) were chosen to be a potential drug carrier. In order to explore the biocompatibility of nano-LDHs with Hela cells, a single cell gel electrophoresis and H2DCF-DA fluorescent coloration assay were used to analyze the DNA damage and the change of reactive oxygen species (ROS) in Hela cells exposed to nano-LDHs. Results showed that, with the increase of concentrations of nano-LDHs (0~800 mu gldrmL-1), the Tail DNA%, Tail Moment and ROS contents in Hela cells increased gradually; there were significant differences (p < 0.05, p < 0.01) in those parameters between high concentration groups (200, 400, 800 mu gldrmL-1) and the control group, while no significant differences (p > 0.05) were found between low concentration groups (50, 100 mu gldrmL-1) and the control. The results suggested that the low concentration nano-LDHs (les 100 mu gldrmL-1) had a good biocompatibility with Hela cells, indicating that nano-LDHs may be applicable in medicine.