Abstract: In sintering process, for melted mineral fines bind unmelted core ores when cooled, the self-intensity of binding phase in iron ores is one of the basic indexes to estimate sintered binding status. With eight kinds of iron ores, the self-intensity characteristic of binding phase was studied at the same temperature and different basicities and their influence factors were theoretically discussed. It is indicated that since different kinds of iron ores have different self-characteristics, the sintering intensity of binding phase and its dependence on basicity have obvious difference. As a result, the sintering intensity of binding phase can be considered as an important technical criterion for optimizing the sintering blending.