The synthesis of multifunctional nanoparticles (NPs) that combine some of the unique physical and chemical characteristics of two or more classes of materials is still a key goal in modern materials chemistry and has attracted substantial interests in recent years. In that context, magnetic monodispersed TiO2 grains filled into spindle-like hematite bi-component NPs were synthesized by ion implantation. The α-Fe2O3/TiO2 bi-component NPs present superparamagnetism at room temperature, and its saturation magnetization was enhanced from 0.53 emu/g (α-Fe2O3 seeds) to 3.55 emu/g. The proposed doping synthesis method allows for fabricating the other bi- or multi-component NPs. The magnetic α-Fe2O3/TiO2 would be acted as “nanoreactors” and provide a promising composite photocatalyst with narrow and wide bandgap semiconductors in the future.