For the first time in the world, we performed the research of the internal structure of dinosaur egg fossil by the use of medical CT scanning. The dinosaur egg fossil came from grand lay of Correlation of the Wangshi Formation, Upper Cretaceous in Lai Yang, Shan Dong. Because of the different internal ingredient of dinosause egg fossil, these exists different density in CT transverse scanning section, so that we can clearly distinguish the structure of egg shell, egg white, egg yolk etc and measure their concrete data. The character of the method is rapid accurate precise and clearly - imaging without damage. It provides a new way for research of dinosaur egg and other ancient living. The results showed the internal structure of dinosaur egg fossil was composed of three parts, that was egg shell, egg while and egg yolk. And we found the embryonic disk of primitire put period in the part of egg whith, so it proved the early embronic development of dinosause is in the edge of egg white near the egg shell with no division of egg yolk.