Abstract: Magnetite nanoparticle is a kind of materials with many functions，and has wide application in such fields as medicine，catalysis and magnetic recording etc. This review summarizes the preparation methods of magnetic magnetite nanoparticles，including co-precipitation，thermal decomposition，microemulsion，and hydrothermal synthesis etc. Current strategies for the protection of magnetic nanoparticles are also discussed，such as surface modification，polymer coating，silica coating，carbon coating，gold coating and so on. Finally，the research prospect of magnetism particles is presented.

摘要： 磁性纳米颗粒是一种多功能性材料，在医学、催化和磁记录材料等领域有着广泛的应用。本文综述了磁性氧化铁纳米颗粒的制备方法，包括共沉淀法、热分解法、微乳液法、水热合成法；改性途径，包括表面活性剂改性、有机聚合物包覆，和硅、碳、金等无机材料包覆的研究现状和最新研究成果，并对其以后的发展方向进行了展望。