Use of probiotics in freshwater fishes is debated for its benefits to the host. Tinfoil barb, Barbonymus schwanenfeldii is a tropical fish having ornamental as well as food value. This study was conducted to evaluate effect of Lactobacillus sporogenes on Tinfoil barb. Diets containing 0%(T0), 0.5%(T1), 1%(T2), 1.5%(T3), and 2% (T4) of probiotic L. sporogenes were prepared and fed to fishes at 3% body weight for 80 days. Control diet was fed to fishes of all treatments for 20 more days. Growth parameters, gut microflora and intestinal histology were analysed. The growth performance was found to be significantly better (P < 0.05) in fishes fed with 1% of probiotic but Survival remained unaffected due to the concentration of probiotic. Total Plate Count of aerobes seemed to be affected by concentration and duration of probiotic treatment. However, anaerobic TPC did not show much variation. Histological analysis revealed that in lower level of incorporation (T2-1%) fish have intact mucosal layer with increased absorptive enterocytes and absorptive area of intestinal villi, well organized lamina propria with different types of cells compared to other treatments. The results indicated that addition of L. sporogenes at 1% level of inclusion was found to be effective for better growth, survival, gut flora as well as intestinal morphology in B. schwanenfeldii.