Abstract: Zebrafish is a small tropical aquarium fish with short generation cycle and high reproductivity. It’s inexpensive and easy to care for in laboratory. Further more, large numbers of embryos can be produced year round and the optically transparent embryos fertilize and develop externally. All these advances have made this small aquarium fish a new “pet” of toxicologists. Zebrafish has been widely utilized in embryonic and developmental toxicology, environmental toxicology, pathological toxicology and pharmaceutical toxicology research.