Dehydroepiandrosterone (DHEA), chemical name is 3 – β– Hydroxyandrosterol – 5 – ene – 17 – one is a kind of cholesterol retaining △ 5,6 double bond and esterifiable 3 – β– The hydroxyl steroid has a molecular formula of C19H28O2, a molecular weight of 288.41, a melting point of 151 to 153 degrees centigrade, and an optical rotation of +5.5 degrees. It is an precursor of adrenal gland hormone secreted by the adrenal cortex reticular layer of the human body. It has the physiological functions of regulating obesity, preventing diabetes, resisting cancer and virus infection, improving memory, immune reaction and stress reaction, and reducing tension. It is an intermediate for the manufacture of steroid hormones and participates in the synthesis of adrenal glands to secrete a variety of hormones.