Purpose of review <p>Fish-mediated allergic diseases are characterized by high prevalence, clinical severity, sensitization potential, and lifelong persistence. Their growing threat to public health has made them a major public health challenge requiring urgent attention. Due to species diversity resulting from evolutionary processes and processing methods, fish consumption patterns vary appreciably across global diets. The molecular structural and physicochemical variations and conservation among different allergens can induce distinct or cross-reactive immunological responses and clinical phenotypes in vivo, posing appreciable challenges to precise clinical diagnosis and personalized treatment. Deepening our understanding of the underlying mechanisms linking these structural characteristics and immune responses will help overcome current clinical difficulties, providing theoretical support and practical guidance for developing more effective allergy prevention and control strategies for the majority of patients.</p> Recent findings <p>Recent studies indicate that fish allergies involve diverse species, with the structural characteristics and conserved nature of antigenic epitopes serving as the core molecular basis for mediating allergies and cross-reactions. Bioinformatics technologies have advanced the identification, analysis, and prediction of fish allergens and antigenic epitopes, providing theoretical support for elucidating sensitization mechanisms and the nature of cross-reactions. Diagnostic techniques have appreciably enhanced specificity and clinical value. Building upon this foundation, hypoallergenic technologies leverage high-temperature processing, enzymatic hydrolysis, fermentation, and other methods to selectively disrupt antigenic epitope structures or reduce allergen content, effectively diminishing their allergenicity. This approach has led to notable progress in the production of hypoallergenic aquatic products.</p> Summary <p>This review focuses on elucidating the key structural and molecular characteristics of fish allergens, emphasizing the immunological mechanisms underlying allergic reactions and the nature of cross-reactivity. It comprehensively reviews the current status and advances in diagnostic and therapeutic technologies, summarizes the developmental trends in the field, and outlines future research directions. By continuously deepening scientific understanding of the biological properties of fish allergens, this work provides additional theoretical foundations and conceptual insights for developing more efficient and precise strategies for allergy prevention, control, and intervention.</p>