Gibbon Interferon-Beta (IFN-β) is a type I interferon produced by virus-infected epithelial cells, fibroblasts, macrophages, and dendritic cells in gibbons (family Hylobatidae), where it functions as a key early mediator of innate antiviral immunity. Highly conserved with human IFN-β due to close phylogenetic relatedness, gibbon IFN-β signals through the type I interferon receptor complex (IFNAR1/IFNAR2), activating JAK/STAT pathways and inducing interferon-stimulated genes (ISGs) that inhibit viral replication, enhance antigen presentation, and promote natural killer (NK) cell and adaptive immune responses. IFN-β plays an important role in host defense against viral pathogens documented in nonhuman primates, including hepatitis viruses, herpesviruses, respiratory viruses, and emerging zoonotic agents. As lesser apes with genetic and immunologic similarity to humans, gibbons provide valuable comparative insight into primate interferon biology, antiviral signaling, and host–virus co-evolution. Characterization of gibbon IFN-β supports research in primate infectious disease susceptibility, conservation medicine, and translational immunology, particularly in understanding species-specific differences in type I interferon regulation, immune activation, and viral pathogenesis relevant to human health.