Abstract: The problem of tax losses in E-commerce has been paid more attention in some countries. In this regard, many scholars in the United States estimated the scale of E-commerce tax losses of the whole nation or relevant states. This paper estimates Chinese E-commerce tax losses by means of average taxation burden method. It is found in this paper that the average loss rate of taxation is about 13 percent in China. Theoretical analysis and numerical simulation is also adopted to analyze relevant factors affecting the implementation of E-commerce tax policy. Finally, this article presents some recommendations to control Chinese E-commerce tax losses.