Abstract: According to the solubility difference of the protopanaxadiol between in chloroform and in water,acidic potassium dichromate solution is used to react with protopanaxadiol in chloroform,then the protopanaxadiol oxide is obtained.\ Protopanaxadiol is synthesized after reduction with the new-made sodium borotritide.The radiochemical purity of the product purified by HPLC is greater than 98%,and its specific activity is 738 GBq/mmol.The quality of the product could meet the demands of the relevant research on medicine or pharmacology.