With the advancement of urbanization process of China, more and more rural labor transfer to urban, the feature of the dual economy in urban becomes more and more obvious. The article reviews the development of the theoretic and empirical studies about the informal employment, and discusses the estimation method of informal employment. On the basis of that, this article estimates the scale and proportion of informal employment in China with the synthetic and residual methods respectively, and analyses the influence of the economic development level, economic growth and other economic factors on the scale and proportion of informal employment. Finally, the direction of further research is advanced. |