Fe3O4@BSA nanoparticles (NPs) were successfully synthesized, and bovine serum albumin (BSA) coating upon the surface of Fe3O4 NPs played the role of stabilizer and disperser. The prepared Fe3O4@BSA NPs were characterized and analyzed by Fourier transform infrared spectra (FTIR), X-ray diffraction (XRD), transmission electron microscopy (TEM) and thermogravimetric analysis (TGA). The results suggested the successful synthesis of Fe3O4@BSA NPs. The content of BSA was about 18.9 % in Fe3O4@BSA NPs. The results of MR imaging in vivo showed that the T2 MRI signals were improved gradually with increased iron concentrations, which presented an obvious negative MRI effect of Fe3O4@BSA NPs. The transverse relaxivity (r2) of the Fe3O4@BSA NPs was evaluated as 148.18 L/(mmol·s) at 0.5 T. These preliminary studies indicated that the obtained Fe3O4@BSA NPs could be used as promising T2 contrast agents for magnetic resonance imaging.