Abstract: With the booming development of electronic information science and 5G communication technology, electromagnetic radiation pollution poses a huge threat and damage to humanity. Developing novel and high-performance electromagnetic wave (EMW) absorbers is an effective method to solve the above issue and has attracted the attention of many researchers. As a typical magnetic material, ferrite plays an important role in the design of high-performance EMW absorbers, and related research focuses on diversified synthesis methods, strong absorption performance, and refined microstructure development. Herein, we focus on the synthesis of ferrites and their composites and introduce recent advances in the high-temperature solid-phase method, sol–gel method, chemical coprecipitation method, and solvent thermal method in the preparation of high-performance EMW absorbers. This review aims to help researchers understand the advantages and disadvantages of ferrite-based EMW absorbers fabricated through these methods. It also provides important guidance and reference for researchers to design high-performance EMW absorption materials based on ferrite.