An optimization model for iron-making system covering sinter matching process to blast furnace process is established, in which the energy consumption, CO_2 emission and cost minimizations are taken as optimization objectives. Some key constraints are considered according to practical production experience in the modelling. The combination of linear programming(LP)and nonlinear programming(NLP) methods is applied. The optimal sinter matching scheme under given conditions and the optimization results for different objectives are obtained. Effects of sinter grade and basicity on all the optimal objectives and coke ratio in blast furnace process are analyzed, respectively. The results obtained indicate that compared with the initial values,the energy consumption/CO_2 emission of iron-making system decreases by 2.03% for objectives of energy consumption/CO_2 emission minimizations and 1.89% for the objective of cost minimization, the cost decreases by 17.88% and 18.13%, respectively.All the three criteria decrease with the increasing lump usage, coal powder injection, blast temperature, and decreasing coke ratio for the iron-making system. An optimization model for iron-making system covering sinter matching process to blast furnace process is established, in which the energy consumption, CO 2 emission and cost minimizations are taken as optimization objectives. Some key constraints are considered according to practical production experience in the modeling. The combination of linear programming (LP) and nonlinear programming (NLP) methods is applied. The optimal sinter matching scheme under given conditions and the optimization results for different objectives are obtained. Effects of sinter grade and basicity on all the optimal objectives and coke ratio in blast furnace process are analyzed, respectively. The results obtained indicate that compared with the initial values, the energy consumption / CO 2 emission of iron-making system decreases by 2.03% for objectives of energy consumption / CO 2 emission minimizations and 1.89% for the objective of cost minimization, the cost decreases by 17.88% and 18.13%, respectively.All th e three criteria decrease with the increasing lump usage, coal powder injection, blast temperature, and decreasing coke ratio for the iron-making system.