Objective:To analyze the ultrastructure of autophagosome. Methods: We used transmission electron microscopy to analyze the cell samples of autophagy, and to find the characteristic structure of the autophagosome, and to identify the other cell structures which was similar to autophagosome. Result: Autophagosome had the characteristics of double layer or multilayer membrane and inclusions, it could be identified from the other cell structure. Conclusion: Double layer or multilayer membrane and inclusions are the characteristics of the autophagosome structure which contains mitochondria, endoplasmic reticulum, ribosome and other cytoplasm components.