Abstract: Printing and dyeing wastewater has a complex composition, in which there are a large number of organic dyes and other pollutants, causing great harm to the environment and human health. Traditional wastewater treatment methods are often difficult to effectively remove these organic pollutants, and in recent years, people have begun to pay attention to the use of nanomaterials to solve this problem. Fe₃O₄ nanomaterials have gradually become a new type of wastewater treatment materials with great prospects for application due to their excellent properties such as magnetism, biocompatibility and optical properties. This paper describes the process of preparing high-quality Fe₃O₄ nanomaterials using physical, chemical, and biological methods, and introduces the methods of modifying them organic, inorganic, and framework materials, etc. to solve the problem of easy agglomeration and improve their stability. The latest research progress on the application of Fe₃O₄ nanomaterials in the field of printing and dyeing wastewater treatment is summarized, and finally, the preparation methods and application studies of Fe₃O₄ nanomaterials are discussed, aiming to provide theoretical references to promote the popularization and application of Fe₃O₄ nanomaterials.