The hydroxy-iron powder with a hollow structure（h-hydroxy-iron，h-HI）were prepared with pitting method, then hollow-HI coated with MWCNTs(MWCNTs@h-HI) were prepared by connecting h-HI and MWCNTs with PABA as the active grafting agent. XRD、SEM、TEM Lakeshore7307VSM were used to characterize the as-prepared products, Hydroxy-iron powder, hollow HI and MWCNTs@HI were also characterized as comparisons. The experimental results showed that the hydroxy-iron powder was successfully prepared and grafted with MWCNTs, the best pitting time was 15min, the wall thicknesses of h-HI particles were 200nm and the thickness of grafting layer were 150nm when the diameters of h-HI particles were about 2μm. The saturation magnetization (Ms) of MWCNTs@h-HI was 140.88emu/g, the remanence(Mr) was 1.48emu/g and the coercivity(Hc) was 47.42G.