Abstract: With the energy-saving targets decomposed to every city, the energy-saving difference of each city needs to be considered for the city government to make energy-saving policies according to its local conditions and for the enterprises to develop energy-saving markets. The difference of each city is mainly affected by the optimization and upgrading stage of the city’s industrial structure. Based on relevant literature and the national planning, this paper proposes a theoretical hypothesis that all cities in the country can be divided into five categories: core city, sub-center city, small- and medium-sized city, tourism-specific city and agricultural-specific city, and each category has its own type of industrial structure upgrading. 281 prefecture-level cities are used to make empirical analysis. The results show that these five types of cities have significant differences in industrial structure changes. It is proposed that attention should be paid to the differences of industrial structure and economic development stages of the five types of cities when the government decomposes energy-saving targets to cities and conducts city energy-saving benchmarking, and when enterprises carry out energy-saving marketing analysis.