Hamster CCL3 (C-C motif chemokine ligand 3, also known as MIP-1α, macrophage inflammatory protein-1 alpha) is a pro-inflammatory chemokine that regulates recruitment and activation of immune cells during inflammatory and infectious responses in hamsters (commonly Mesocricetus auratus and Phodopus spp.). CCL3 primarily signals through the CCR1 and CCR5 receptors, promoting chemotaxis of monocytes, macrophages, dendritic cells, natural killer (NK) cells, and activated T lymphocytes to sites of infection or tissue injury. In hamsters, CCL3 is produced by activated macrophages, dendritic cells, epithelial cells, and lymphocytes in response to inflammatory stimuli such as pathogen-associated molecules and cytokines including TNF-α and IL-1β. In research, CCL3 is particularly relevant in hamster models of viral and inflammatory diseases, including SARS-CoV-2 and other respiratory viral infections, where recruitment of monocytes and macrophages to lung tissue contributes to antiviral immune responses and inflammatory lung pathology. While CCL3-mediated leukocyte trafficking supports pathogen clearance and immune activation, excessive or prolonged expression may contribute to tissue inflammation and damage. Because hamsters are widely used as translational models for respiratory viral infection, inflammation, and immunopathology, characterization of hamster CCL3 supports studies of chemokine-driven immune cell migration, host–pathogen interactions, and mechanisms regulating inflammatory responses relevant to human disease.