Abstract: With the intensified exploration of marine resources, marine bioactive peptides have become one of the research focuses in biomedicine, food science, and materials science because of their structural diversity, unique biological activities, and broad application potential. At present, the extraction of marine peptides has expanded beyond conventional chemical extraction and enzymatic hydrolysis, with microbial fermentation and gastrointestinal simulation technologies further broadening peptide diversity. In addition, the integration of multiple chromatographic techniques with advanced detectors has significantly improved the efficiency of marine peptide identification. Owing to their diverse biological activities, including immunoregulatory, antioxidant, antibacterial, antitumor, hypotensive, and hypoglycemic effects, marine peptides not only enrich the pool of candidates for marine drug development but also provide new perspectives for addressing numerous health challenges. Importantly, substantial progress has been made in the screening, identification, and mechanistic elucidation of marine bioactive peptides, driven by advances in high-throughput technologies and the bioinformatics. However, marine peptide research still faces several challenges, including complex sourcing, difficulties in large-scale acquisition, and insufficient exploration of biological activities. Therefore, this article concisely reviews recent progress in the extraction, purification, and identification of marine bioactive peptides, summarizes current research on their biological activities, and highlights the application of bioinformatics in marine peptide studies.