Abstract: Effective antifouling techniques are absolutely important since marine biofouling seriously compromises the performance and service lifetime of ships and underwater equipment. Through the release of harmful biocides, conventional antifouling coatings seriously endanger marine ecosystems and biodiversity. In response, functional polymer brush coatings, which produce antifouling effects without releasing biocides, have taken front stage in recent years. Under the dual needs of sustainable resource use and marine ecological conservation, this review focuses on the synthesis and development of four functional polymer brush coatings, including fouling-resistant, fouling-release, fouling-degrading, and dynamic surface antifouling coatings. This review also considers future directions of research and development trends for environmentally friendly antifouling technology.