In the nuclear waste processing, reduction of highly toxic and mobility radioactive U(Ⅵ) to low toxicity and mobility radioactive nuclide uranium U( Ⅵ) is proposed as a very critical process step to remediate U-contaminated. Zero-valent iron (ZVI) reduction technology show a good application prospect for reduction of radioactive nuclide uranium U(Ⅵ) because of its low apparatus cost, environmentally friendly and easy operation, ect. This paper is written for discussing the three kinds of interface chemical mechanism between U(Ⅵ) and zero-valent iron in detail: reduction precipitation mechanism, adsorption mechanism and coprecipitation mechanism. In addition, the water chemistry factors on this mechanism such as redox conditions, medium pH, co-existent ions, natural organic matter and microorganism are deeply analyzed, and the further research on how to effectively and deeply carry out the research on the remediation of U(Ⅵ) by zero-valent iron is also discussed.%在核废料处理中,如何将毒性大、易迁移的放射性核素U(Ⅵ)转化为毒性小、难迁移的U(Ⅳ)是非常关键的处理步骤.零价铁还原技术由于其价格廉价、环境友好、工艺简单等优点,在放射性核素U(Ⅵ)的还原处理方面也显示了较好的应用前景.本文详细地论述了零价铁去除U(Ⅵ)的3种界面化学作用机理:还原沉淀机理、吸附机理、共沉淀机理；还就各种水化学因素:氧化还原条件、介质pH、共存离子、天然有机质及微生物等对反应作用机理的影响进行了较为深入的讨论；并对如何有效、深入开展零价铁去除U(Ⅵ)的今后研究方向进行了展望.
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