Bovine Interferon-Beta (IFN-β) is a type I interferon produced primarily by virus-infected epithelial cells, fibroblasts, macrophages, and dendritic cells in cattle (Bos taurus), where it serves as a key early mediator of innate antiviral immunity. Following recognition of viral nucleic acids by pattern recognition receptors such as RIG-I–like receptors and the cGAS-STING pathway, bovine 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 inhibit viral replication, enhance antigen presentation, and promote natural killer (NK) cell and adaptive immune activation. IFN-β plays an important role in host defense against economically significant bovine viral pathogens including bovine viral diarrhea virus (BVDV), bovine herpesvirus-1 (IBR), bovine respiratory syncytial virus (BRSV), foot-and-mouth disease virus (FMDV), and other agents involved in the bovine respiratory disease (BRD) complex. Many of these viruses possess immune evasion strategies that suppress or delay IFN-β production, contributing to viral persistence and disease severity. As both a biomarker and functional mediator of antiviral responses, bovine IFN-β is central to vaccine evaluation, antiviral research, and studies of host–virus interactions in cattle, while also supporting comparative research into type I interferon biology in large-animal models relevant to human infectious disease.