As men age, a growing number develop benign prostatic hyperplasia (BPH). According to previous research, diabetes may be a risk factor. Pyruvate dehydrogenase kinase 4 (PDK4) is closely related to glucose metabolism and plays a role in the onset and progression of numerous illnesses. This study aimed to determine the direct effects of high glucose environment on prostate epithelial cells, in particular by altering PDK4 expression levels. In this investigation, normal prostatic epithelial cells (RWPE-1) and human benign prostatic hyperplasia epithelial cells (BPH-1) were treated with 50 mM glucose to show the alteration of high glucose in prostate cells. PDK4-target siRNA, PDK4-expression plasmid were used to investigate the effects of PDK4. Rosiglitazone (RG), a PPARγ agonist, with the potential to up-regulate PDK4 expression was also used for treating prostate cells. The expression of PDK4 in human prostate samples was also analyzed. The effects of high glucose therapy on BPH-1 and RWPE-1 cells were demonstrated to enhance proliferation, epithelial-mesenchymal transition (EMT), suppress apoptosis, and down-regulate PDK4 expression. Additionally, diabetes-related BPH patients had reduced PDK4 expression. Following the application of PDK4-target siRNA, a comparable outcome was seen. The PDK4-expression plasmid therapy, however, produced the opposite results. RG with the ability to elevate PDK4 expression might be used to treat BPH. Changes in the metabolism of lipids and glucose may be the cause of these consequences. These findings showed that high glucose treatment might facilitate BPH development, and may be related to the down-regulation of PDK4. PDK4 might be a potential therapeutic target of BPH.© 2023. Springer Nature Limited.