By loading doxorubicin (DOX) on 5-carboxyl-fluorescein (FAM) labeled AGKGTPSLETTP peptide (A54) coupled starch-coated iron oxide nanoparticles (SIONs), we prepared a novel aqueous drug delivery system with both magnetic and biomolecular targeting, which was specific to human hepatocellular carcinoma cell line BEL-7402. The saturated extent of adsorption reached 2.0 mg DOX/mg A54-SIONs at 28 degrees C, which provided a rather high dose of DOX loading for application. Tests in vitro demonstrated the specificity of DOX-loaded A54-SIONs to BEL-7402 cells. The microscopy images proved that DOX-loaded A54-SIONs were successfully targeted to tumor tissue of nude mice with an external magnetic field in vivo. MTT assay showed higher cytostatic effect of DOX-loaded A54-SIONs to hepatocellular carcinoma cells BEL-7402 than that of DOX-loaded SIONs.