PDK (Pyruvate Dehydrogenase Kinase) is a group of kinases that regulate the activity of the key enzyme pyruvate dehydrogenase complex (PDH) in glycolysis and gluconeogenesis processes. The PDK family includes four isoforms: PDK1, PDK2, PDK3, and PDK4, mainly located on the inner membrane of mitochondria. They inhibit the PDH complex through phosphorylation, reducing pyruvate entry into the citric acid cycle, thus affecting energy metabolism. The expression of each family member has tissue specificity; for example, PDK4 is highly expressed in the liver and muscle during fasting. Mutations and abnormal expressions of PDK genes are related to the occurrence and development of various diseases, such as diabetes and cardiovascular diseases.