Feline angiogenin (ANG) is a secreted ribonuclease belonging to the RNase A superfamily that plays a central role in angiogenesis, tissue remodeling, and cellular stress responses. In cats (Felis catus), angiogenin is produced by endothelial cells, epithelial cells, macrophages, and tumor cells, where it promotes endothelial cell proliferation, migration, and new blood vessel formation through interactions with cell surface receptors and activation of pro-angiogenic signaling pathways. Beyond its vascular effects, angiogenin is also involved in regulation of RNA metabolism, cellular survival under stress conditions, and modulation of innate immune responses. Baseline circulating levels in healthy cats are typically low to moderate, but expression may increase during neoplastic disease (such as lymphoma and mammary carcinoma), chronic inflammation, wound healing, hypoxia, and renal or cardiovascular pathology. In veterinary and comparative medicine research, feline angiogenin serves as a biomarker of angiogenic activity, tumor progression, and tissue repair, and is of particular interest in studies of cancer biology, inflammatory disease, and vascular remodeling in both clinical feline patients and translational oncology models.