Objective：This study aims to investigate the diagnostic efficacy of targeted magnetic resonance SPIO - PLA - P53 molecular probe in rat glioma. Methods：Superparamagnetic iron oxide nanoparticles SPIO -PLA and glioma targeting nanomolecular probe SPIO-PLA-P53 were synthesized. The physical properties of molecular probes were detected by transmission electron microscopy and dynamic light scattering. Cell activity was detected by Cell Counting Kit - 8(CCK - 8)method. The penetration efficiency of molecular probe through blood-brain barrier in vitro was detected. The distribution of nanoprobes in glioma was detected by 7.0 T small animal - special magnetic resonance instrument and matching coil. Pathological staining of tumor - bearing mouse brain tissue was performed to clarify the accumulation of targeted molecular probes in the tumor tissue. Statistical analysis of the results was performed using GraphPad Prism software. Results：Glioma targeted SPIO - PLA - P53 nanoparticles have uniform size，good dispersion，good biocompatibility and targeted aggregation effect. Magnetic resonance scanning showed that the tumor T2WI signal was decreased after injection of targeted SPIO - PLA - P53 probe in the tumor - bearing rats，and there was no significant change in the tumor signal after injection of SPIO-PLA probe solution. The pathological results confirmed that a large amount of iron ions accumulated in the glioma of rat injected with SPIO -PLA -P53. Conclusion：SPIO -PLA -P53 can be used as an magnetic resonance molecular probe for specific imaging of rat gliomas.