Abstract: China is a country with coal and electricity sources as the mainstay. How to optimize the energy structure has become the focus of supply-side reform.Taking the production efficiency of enterprises as the starting point,the vertical integration of China's coal-electricity industrial chain is subdivided into the forward integration of the coal industry and the backward integration of the power industry. Based on the micro-enterprise data from 2002 to 2017,the vertical integration index is calculated by the input-output table method,and the TFP of coal and electricity enterprises is measured by the semi-parametric estimation method with the intermediate input as the proxy variable. And further construct a fixed effect panel model to analyze the impact of vertical integration on enterprise TFP. Research indicates:(1)The forward integration index of the coal industry and the backward integration index of the power industry both fluctuated,but the latter's upward trend was higher than the former.(2)The TFP of the coal-electricity industrial chain shows a volatility,and the TFP of the power industry is higher than that of the coal industry.(3)The vertical integration policy of coal-electricity industrial chain has an "inverted U-shaped" relationship with the TFP of enterprises. However,the integration of coal and electricity enterprises still has a positive impact on improving production efficiency.