In this paper, the correction coefficient was applied to measure energy industry efficiency of emission reduction in each province. According to the energy industry carbon emission intensity and output value share of each province, the identity of national carbon emission intensity in China's energy industry was established from top to bottom, and the contribution rate of each province, energy industry carbon emission intensity and output value share in each province to the decline of national carbon emission intensity in energy industry was obtained by using LMDI-I decomposition method. Following the idea of “emission reduction efficiency - carbon emission intensity contribution - comprehensive contribution by province - the relationship between provincial emission reduction efficiency and the comprehensive contribution of province”, the emission reduction effectiveness of each province in the process of carbon emission intensity decline in China energy industry was evaluated. The results indicate that (1) the carbon emission intensity in China' energy industry shows a downward trend year by year, and the carbon emission intensity decreased by 45% in 2016 than that in 2005. (2) More than half of the provinces are efficiency areas for emission reduction and the number of provinces is increasing, while most of the provinces that do not meet the emission reduction standards are located in economically underdeveloped areas, and there are significant differences in emission reduction paths between provinces. (3) The contribution rate of energy industry carbon emission intensity in most provinces shows an upward trend, and the regional differences gradually decrease. (4) The competing momentum of comprehensive contribution by province is strong, and most provinces have contributed to the decline of carbon emission intensity in China energy industry, and the eastern region is the main contribution area, where the comprehensive contribution grade of many provinces develops positively. (5) The number of provinces with good emission reduction effectiveness is the largest, the general areas are scattered in the eastern coastal area and a few inland areas, and the spatial pattern of the poor areas remains stable in the western region. In the future, provinces should not only choose the low-carbon development path according to their own emission reduction effectiveness characteristics, but also form a benign interaction with the decline of national carbon emission intensity.