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Hierarchically mesoporous silica coated superparamagnetic microspheres with an uniform particle diameter of 750-800 nm and shell thickness of 65-100 nm were synthesized utilizing the surfactant-templated coating process using ethanol as cosolvent and CTAB as surfactant.The obtained materials were highly magnetic with large saturation magnetization.Hierarchically mesoporous silica shell structures were obtained with the aid of organic swelling agent TMB at the TMB/CTAB molar ratios above 0.6.Three kinds of porosities with peak pore sizes of 3.3 nm,5.3 nm,and that larger than 10 nm coexisted in the mesoporous shell due to the inhomogeneous distribution of TMB in CTAB micelles and disordered packing of mesophase by the influence of ethanol.The surface area gradually decreased and the total pore volume first decreased then increased with the increase of TMB/CTAB molar ratio.These hierarchically mesoporous silica coated superparamagnetic microspheres are believed to be highly potential in magnetic targeted delivery of multiple biomolecules with different molecular sizes.