To evaluate the ecotoxicity of nanomaterials, zebrafish embryos were selected as biological subjects, the toxicity of nano-ZnO, nano-TiO₂ and carbon nanotubes on zebrafish embryos hatching rate and teratogenic rate were assessed. Zebrafish embryos of 1 h post fertilization were exposed to a series of different concentrations of nanomaterial solutions, and hatching rate and cumulative hatchability at 36-96 h were recorded. The results showed although Zn2+ has dissolved, But little effect on hatchability,nano-ZnO was more significant inhibition on embryo hatching, in 50 and 100 mg／L nano-ZnO exposure group. Nano-ZnO also causing pericardial edema. Carbon nanotubes did not affect hatching rate but might cause hatching delay, and exert concentration-dose relationship. In the range of this experimental concentrations, acute exposure nano-TiO₂ has no significant influence on hatching rate and malformation rate.