This research studied the transformation of ursolic acid by some microorganism in order to modify its structure. Through the incubation of ursolic acid with the endophytic fungus isolated from six different kinds of loquat leaves, the loquat leaf endophytic fungus1 founded in loquat leaf Narrow leaf, Jiefangzhong and Mogi can transform the ursolic acid to a Terpenoid compound. By incubation of ursolic acid with metarhizium anisopliae, a acicular crystal was obtained with the melting point being of 202~205 ℃ and high solubility in methanol. The crystal was then preliminarily analyzed.