EHHADH, as the "bifunctional catalytic center" of peroxisome fatty acid β-oxidation, its expression and activity directly affect energy metabolism, inflammation level and cell fate. Gene defect causes serious neuro-renal tubular lesions, and abnormal expression is closely related to modern chronic diseases such as obesity, diabetes and tumor, which is one of the hot metabolic enzymes concerned by basic research and clinical transformation. It is mainly located in peroxisome, and some activity can be detected in mitochondrial inner membrane, and it is highly expressed in liver, kidney, heart and other organs.