Hamster CCL5 (C–C motif chemokine ligand 5, also known as RANTES – Regulated upon Activation, Normal T cell Expressed and Secreted) is a proinflammatory chemokine that regulates immune cell recruitment and inflammatory responses in hamsters (e.g., Mesocricetus auratus). CCL5 is a member of the CC chemokine family, which also includes CCL3 (MIP-1α), CCL4 (MIP-1β), and CCL2 (MCP-1), chemokines that coordinate leukocyte trafficking during immune activation. In hamsters, CCL5 is produced primarily by activated T lymphocytes, macrophages, dendritic cells, platelets, and epithelial cells in response to infection, inflammatory stimuli, or tissue injury, and it exerts its biological effects mainly through binding to the chemokine receptors CCR1, CCR3, and CCR5, promoting chemotaxis and activation of T cells, monocytes/macrophages, eosinophils, and natural killer (NK) cells at sites of infection or inflammation. Hamsters are widely used as animal models for infectious diseases, including SARS-CoV-2, hantavirus, and other respiratory viral infections, where chemokines such as CCL5 contribute to recruitment of immune cells to infected tissues and regulation of antiviral inflammatory responses. Consequently, hamster CCL5 is frequently studied in immunology, infectious disease, and vaccine research, helping to elucidate mechanisms of chemokine-mediated immune cell trafficking and host defense in disease models relevant to human health.