¹Institute of Animal Husbandry and Veterinary Science, Shanghai Academy of Agricultural Science, Shanghai, 201106, P. R. CHINA DOI : 10.9775/kvfd.2023.29134 As antibiotics are now prohibited or heavily regulated in farming in most countries, nutritionists and veterinarians are increasingly turning to probiotic supplements, prebiotics, and synbiotics to promote animal health and improve production performance. The study aimed to evaluate the effects of Bacillus subtilis, fructooligosaccharides (FOS), and their combined use on geese, compared to antibiotics, and evaluate their suitability as an alternative to antibiotics. 240 14-day-old geese were randomly divided into five groups and were fed a basal diet or supplemented with 100 mg/kg chlortetracycline, 400 mg/kg FOS, 2x105cfu g/kg B. subtilis, or a combination of 200 mg/kg FOS and 1x105cfu g/kg B. subtilis for 56 days. The study measured the body weight, feed consumption, serum parameters, and intestinal morphology of the geese. The results showed that the combination of B. subtilis and FOS had a positive impact on the body weight, feed consumption, and serum parameters of the geese, while improving their intestinal morphology. The results suggest that the combination of B. subtilis and FOS may provide multiple benefits to animal health and performance and could be used as a suitable alternative to antibiotics. Keywords : Bacillus subtilis, Fructooligosaccharide, Goose, Intestinal morphology, Performance parameters, Serum