BACKGROUND: The use of probiotic bacteria has been suggested as an important strategy to accomplish reproducible outputs through biocontrol in cultivation systems for marine fish larvae and crustaceans. These bacteria have beneficial effects on fish larvae. OBJECTIVES: This study was done to determine the effect of probiotic lactobacilli on the growth and feeding performance of Persian Sturgeon (Acipenser persicus) larvae via bioencapsulation with Daphnia magna. METHODS: Daphnia magna was enriched by probiotic lactobacillus for 8 hours in three levels of 4.30, 4.60 and 4.78 log of colonies forming unit per milliliter in suspension of broth, and fed by A. persicus larvae in experimental treatments (treatments of T1, T2 and T3). The Persian sturgeon larvae were fed on D. magna on the base of 30 percent of their body weight for 30 days. The control treatment was fed on unbioencapsulated D. magna. At the termination of the experiment, the whole body samples of the fish were analyzed according to the AOAC procedures (1990). RESULTS: The probiotic lactobacillus significantly promoted the body weight, levels of crude protein and carcass dry matter of larvae in experimental treatments in comparison with control treatment (p<0.05). But in the treatment T3, the crude lipid and crude energy were significantly decreased (p<0.05). The maximum level of average crude protein in T3 (70.27±0.44 %) and its minimum in control (68.51±0.34%) were obtained. CONCLUSIONS: This study indicated that the blend of Lactobacillus had an effect on the promotion of some of the growth and feeding parameters in Persian sturgeon larvae.