Shikimic acid (SA),the main secondary product of Star Anise (lllicium verum Hook.f.),has significant anti-tumor activity,unique insecticidal mode of action,and is the key intermediate for "Tamiflu" which is special synthetic anti-flu drug.Due to the break out of avian influenza in the world,Star Anise yielding in China presents important medicinal value.This paper studied on the microbial factors of transforming the SA in star anise residua.This study used a special bacteria B31 isolated from the residue in the Star Anise,explore the microbial transformation factors.The analysis results of HPLC showed that the bacterial B31 was incapable of self-production of SA,nor with the 2 % mass concentration of SA saccharide.