The applicability of crossflow microfiltration (CFMF) to the removal of metal ions from liquid solutions was studied. Three treatment processes were employed in this study. The first process was filtration of liquid solutions containing metal ions by CFMF. The second process was CFMF with membranes precoated by CaCO3 cake, The third process used suspension flocculation as a pretreatment step before CFMF. It was found that CFMF or CFMF with precoated membranes could not remove the metal ions (Cu2+, Mn2+ and Fe2+) from water efficiently. On the contrary, CFMF with suspension flocculation as a pretreatment Could remove the metal ions from water completely under suitable pH values. The unsteady-state permeate flux for CFMF with suspension flocculation increased with an increase in temperature but decreased with an increase in pH of the liquid solutions. In addition, an optimal permeate flux existed in the relationship among the permeate flux, crossflow velocity, membrane pore size, and pressure drop. Furthermore, the unsteady-state permeate flux obtained experimentally for CFMF with suspension flocculation could be predicted by a mathematical model developed previously if an equivalent diameter of the flocs in the suspension was used in the model.