Abstract: Combined with the actual temperature of sintering production and comprehensively taking the assimilation process parameters into consideration, the "assimilation characteristic number" is used to characterize the iron ore powder assimilability in tests, which is more accurate and more feasible. Ten kinds of iron ore powder containing 4 % Jing De coke of 30~50 purpose are selected, and the "assimilation characteristic number" is used to characterize their assimilability to determine their respective assimilation characteristic parameters and to analyze their influence factors by combining with their physico-chemical properties. The results show that different kinds of iron ore powder have significant different assimilation characteristic parameters; the major influencing factors include the types of iron ore powder, chemical composition, burning loss and microstructure, etc. Generally speaking, limonite and hematite have good assimilability; SiO₂ has no obvious influence on assimilability; with increasing of the content of Al₂O₃ and MgO, the assimilability increases at first and then decreases, and the powder has the strongest assimilability when the two component contents are moderate; assimilability correlates positively with the burning loss; the powder with loose granular organization has strong assimilability, and powder with dense block organization has weak assimilability.