Abstract: We optimize the Ganoderma lucidum mycelium's fermentation conditions of high triterpenoids production with adding oleic acid,to induce the synthesis of triterpenoids and boost production.In this research,we screened the single factors such as carbon source and nitrogen source,and the optimization of the culture medium was optimized by CCD experiment,we also screened the single factors of fermentation conditions. This research showed that the optimal results were: soluble starch 3.4%,fish peptone 0.72%,KH2PO40.3 %,Mg SO40.15 %,VB10.005 %( m / v),p H5.5,and adding 4.38 %( v / v) of oleic acid at the first day of the fermentation. The liquid loading was 100 m L,the inoculation concentration was 10%( v / v),and the fermentation time was 9 d. And the production of triterpenoids was up to( 287.67 ± 3.77) mg /100 m L. This method not only induced the synthesis of triterpenoids and boost production,but also had important significance for the industrial production of Ganoderma lucidum.