The branched-chain amino acids (BCAAs) Ile, Leu and Val are three out of the nine essential amino acids that plants, unlike many other eukaryotes, can synthesize de novo. BCAAs are of high nutritional value to humans. In plants, BCAAs and BCAA-derived secondary metabolites, such as glucosinolates, are important for plant growth, development, and defence. In addition, BCAAs serve as an alternative energy source for respiration, particularly under carbon-limiting conditions, such as drought or dark-induced senescence. De novo biosynthesis of BCAA in plants is restricted to plastids, whereas BCAAs are catabolised in mitochondria and peroxisomes. Regulation of BCAA homeostasis is important for plant growth and development. Mutants impaired in BCAA catabolism accumulate free BCAA in desiccated seeds and display accelerated senescence under carbon starvation conditions. Despite the extensive research on BCAA catabolism and its regulation in the past years, our understanding of BCAA transport across the inner mitochondrial membrane in plants remains limited. Recently, a mitochondrial BCAA transporter has been described in humans. It imports BCAAs from the cytosol for BCAA catabolism via the branched-chain α-keto acid dehydrogenase complex, thereby actively contributing to human health. Here, we present molecular and functional characterization of the closest homologues in Arabidopsis and their role in BCAA catabolism.