Kruppel-like factor 6 is a DNA-binding protein containing a triple zinc-fingered motif and plays a key role in the regulation of cell proliferation, differentiation and development. More recently it has been implicated in hepatic fibrosis via its binding to the transforming growth factor control element. In the kidney, epithelial to mesenchymal transition is a major contributor to the pathogenesis of renal fibrosis, with TGF-1 being a key mediator of EMT. The present study aimed to determine the role of KLF-6 and TGF-1 in EMT in proximal tubule cells. To determine the relevance in clinical disease, KLF6 was measured in kidneys of streptozotocin-induced diabetic ren-2 rats and in cells exposed to high (30mM) glucose. TGF-1 was confirmed to induce EMT by morphological change, loss of E-cadherin, and gain in vimentin expression. KLF-6 mRNA expression was concomitantly measured. To determine the role of KLF6 in EMT, the above markers of EMT were determined in KLF6 silenced (siRNA) and KLF6 over-expressing proximal tubule cells. KLF6 over-expression significantly promoted a phenotype consistent with EMT. High glucose induced KLF6 in proximal tubule cells (P<0.05). This increase in KLF6 in response to high glucose was TGF-1mediated. In an in vivo model of diabetic nephropathy KLF6 increased at week 4 (P<0.05). KLF6 plays a permissive role in TGF-1-induced EMT in proximal tubule cells. Its up-regulation in in vivo models of diabetic nephropathy suggests it as a potential therapeutic target.