Abstract: Renal fibrosis is a critical pathological process in the progression of chronic kidney disease to end-stage renal disease, characterized by excessive deposition of extracellular matrix, leading to structural destruction and functional loss of the kidney. As a class of essential amino acids, branched-chain amino acid (BCAA) is critical for maintaining protein homeostasis, modulating energy metabolism, and regulating cellular signaling pathways. Dysregulation of BCAA metabolism can contribute to disease pathogenesis through multiple mechanisms. Emerging evidence suggests that BCAA metabolic dysregulation participates in renal fibrosis progression via mechanisms such as inflammation and oxidative stress, metabolic reprogramming and energy dysfunction, epithelial-mesenchymal transition, and gut microbiota dysbiosis. This article systematically reviews the relationship between BCAA metabolic dysregulation and renal fibrosis from two perspectives: the dysregulation of BCAA metabolism and its mechanistic roles in renal fibrosis pathogenesis. Furthermore, we discuss the clinical potential of modulating BCAA homeostasis or intervening in downstream signaling pathways to attenuate renal fibrosis progression.