BACKGROUND: Lactococcus lactis is one of the lactic acid bacteria that can be considered as a probiotic in Persian sturgeon. OBJECTIVES: The aim of the present study was to increase the resistance to Aeromonas hydrophila after feeding the L. lactis JF831150. METHODS: In the present study, first 60 fish were fed different doses of L.lactis JF831150 for 56 days. The bacterial flora were counted with  TSA and MRS. Resistance of fish against A. hydrophila were considered after feeding. RESULTS: The use of L. lactis JF831150 for 56 days in P. sturgeon showed significant improvement in decreasing heterotrophic aerobic bacteria flora and increasing the lactic acid bacteria in the intestine. In the face of fish against A. hydrophila in third treatment (108 CFU/g), the survival rate was shown to be significantly higher than the control and other treatments. CONCLUSIONS: The results showed that consumption of L. lactis JF831150 (108 CFU/g) could improve the intestinal flora and increase resistance to A. hydrophila, and therefore has  potential for use  with P. sturgeon.