<p>Photocatalytic marine antifouling (PMAF) is a raising environmentally-friendly technology and holds promise for balancing economy, efficiency and sustainability. This review systematically summarizes the progress, challenge, and prospect of PMAF, following the technology chain of antifouling principle, material system, and performance promotion. For antifouling principle, the advances of PMAF is elucidated by combining marine biofouling characteristic and photocatalytic antibacterial mechanism. For material system, the types of PMAF materials currently focused on are summarized to guide future directions on cooperation and synergistic research between different materials. For performance promotion, key aspects are discussed from macroscopic crystal-scale morphology to microscopic atom-scale vacancy and electron-scale band, revealing their structure–function relationships. It is hoped that this review will stimulate thinking on the design and optimization of marine antifouling photocatalysts, thereby promoting the practical application of PMAF.</p>