In order to improve bile salt tolerance in L. fermentum, four BSH genes (BSH1,BSH2,BSH3, and BSH4) from L. plantarum AR113 were transformed into L. fermentum AR497. The result showed that heterologous expression of these four BSHs can improve the bile salt tolerance of L. fermentum. At the concentration of 2.0 mg/mL sodium glycodeoxycholate, engineered L. fermentumwith BSH2 expression had the lowest lethality, while other strains were completely inhibited. BSH activity showed that BSH2 expressing strain had the highest enzyme activity with 57.74 U/mL, which was 2.88 times higher than that of the control strain harboring empty plasmid.