In order to investigate the relationship between the properties of iron ore powders and filtration performance, the chemical composition, specific surface area, density, surface morphology, maximum molecular water and maximum capillary water of five kinds of iron ore powders A, B, C, D and E with the same particle size were studied. Filtration experiments were carried out under pressure of 0.06MPa for 3 minutes. The results show that the filter cake moisture, maximum molecular water and maximum capillary water of five mineral powder are in the same order from small to large. And the mineral powder particles with rougher surface, the above three results are higher, otherwise the three results are lower. The burning reduction and FeO content of the ore powder, specific surface area are related to the moisture content of filter cake. There is only a limited correlation between density and moisture content of filter cake.