Ferret Interferon-Beta (IFN-β) is a type I interferon produced primarily by virus-infected respiratory epithelial cells, fibroblasts, macrophages, and dendritic cells in ferrets (Mustela putorius furo), where it serves as a critical early mediator of innate antiviral immunity. Upon recognition of viral RNA by pattern recognition receptors such as RIG-I and MDA5, IFN-β is rapidly induced and signals through the type I interferon receptor complex (IFNAR1/IFNAR2), activating JAK/STAT pathways and driving expression of interferon-stimulated genes (ISGs) that suppress viral replication, enhance antigen presentation, and promote natural killer (NK) cell and adaptive immune activation. IFN-β responses are central to ferret models of respiratory viral infections, including influenza A virus, SARS-CoV-2, respiratory syncytial virus (RSV), and other emerging pathogens, where the timing and magnitude of IFN-β production influence viral load, lung inflammation, and disease severity. Because ferrets are widely regarded as a gold-standard animal model for human respiratory virus transmission and pathogenesis studies, characterization of ferret IFN-β is essential for evaluating antiviral therapeutics, vaccine efficacy, interferon-based treatments, and mechanisms of interferon-mediated immunopathology. As both a biomarker and functional regulator of host–virus interactions, ferret IFN-β plays a central role in translational respiratory disease research and pandemic preparedness efforts.