By adding the production, usage, export and loss of byproducts flows, an improved enterprise inputoutput model was proposed first, which could fully reflect the interactions of material and energy flows and more accurately calculate the products’ embodied energy and total energy consumption. Then, the sensitivity analysis based on the developed inputoutput model was established to calculate the influences of final demand and technical coefficients on the total energy consumption. It helps to identify the key coefficients on the energy consumption. The products’ embodied energy and total energy consumption of Xiangtan Steel Plant was obtained and analyzed. The results show that more than 90% of the total energy consumption is from fossil fuel while the upstream energy consumption of the purchased raw materials contributes to less than 10%; the byproducts utilizations could reduce the total energy consumption by 62.5%; the specific consumption of the washed coal in coke oven, the coke ratio of blast furnace (BF), the specific consumption of hot metal in 1# basic oxygen furnace, the yield rate of ironcontaining products and the technology improvement of BF (e.g. specific consumption of sinter and gas production rate) are the most important coefficients for the change of energy consumption.