Background:The mixed oxide (MOX) fuel is made from UO2 and PuO2 by post-processing of the spent duel of pressed water reactor (PWR). It has a good future for wide application but needs plenty of analyses of its characteristics prior to being used in the reactor.Purpose: This study aims to analyze the radiation characteristics of MOX fuel compared with the traditional core fuel.Methods: In accordance with the fuel management of M310 nuclear power plant (NPP) with 30% core filled with MOX fuel assemblies, fast neutron fluence, displacement per atom (DPA) rate on reactor pressure vessel (RPV) and forward factor of irradiation surveillance of the reactor core are studied and compared with both the traditional high leak reactor core with UO2 assemblies in equilibrium cycle and the low leak reactor core with UO2 assemblies which is minority in China.Results: The former comparison results show that the change of the fast neutron fluence and DPA rate on RPV are decreased by 20%, the fluence rate of irradiation surveillance in the direction of 343° is decreased by 8%, forward factor of irradiation surveillance in the direction of 343° is increased by 15%. The latter comparison results show that the change of the fast neutron fluence and DPA rate on RPV are increased by about 40%. Comparing the MOX fuel with the UO2 fuel on the same power level independently, it shows that MOX fuel releases 7% more fast neutron than UO2 fuel.Conclusion: The reactor core with MOX assemblies has less damage than the traditional high leak reactor core with UO2 assemblies.%U-Pu混合氧化物(Mixed oxide, MOX)燃料应用前景广阔。以国内M310型堆芯为对象，对使用30% MOX燃料的部分低泄漏堆芯燃料管理方案进行分析，比较了含 MOX 燃料堆芯和传统的全 UO2燃料堆芯在平衡循环下压力容器快中子注量、原子位移次数(Displacement per atom, DPA)和辐照监督管超前因子的特性差异。结果表明，与国内主流的高泄漏全UO2燃料堆芯平衡循环相比，平衡循环压力容器内表面快中子注量率和DPA率小20%左右，343°处的辐照监督管快中子注量率小8%，超前因子大15%；与国内占少数比例的低泄漏全UO2燃料堆芯平衡循环相比，平衡循环压力容器内表面快中子注量率和DPA率大40%左右。进一步分析发现，虽然同等功率下MOX燃料比UO2燃料释放的中子多7%，但与国内主流的高泄漏全UO2燃料堆芯相比，部分低泄漏MOX燃料堆芯的燃料管理方式使堆芯外围组件功率降低，使得压力容器受到的快中子辐照损伤降低。
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