In this experiment, "Yufanqie 6" was used as the test material, tomato seedlings were irrigated with different concentrations of BSFA in nutrient solution, and the nutritional solution was used as the control to investigate the morphological and physiological indicators of tomato. The morphological and physiological indexes of tomato were investigated. The results showed that different concentrations of BSFA all promoted the growth of tomato seedling. BSFA promoted the plant height, stem diameter, leaf area, maximum root length, root volume, dry weight and fresh weight of tomato seedling. Compared with the control, the seedling index of each treatment increased 11.11%-47.22%, and the treatment of 80 mg/kg BSFA treatment had the best effect in promoting the growth of tomato seedling.