The effects of supplementation Bacillus S11, a probiotics diets on spotted babylon were conducted for growth and survival determination. Diets were divided into five different groups: Control diet (non-supplemented), diets with fresh cell of Bacillus S11 supplementation at ratios of 1:2, 1:5 and 1:10 (Bacillus/diet w/w) and fresh fish (Selaroides leptolepis). The snails with initial average shell length of 1.14 ± 0.10 cm and weight of 0.3 ± 0.1 g were stocked at a density of 214 individuals per m² in aquaria with a closed recirculating seawater system for 4 months. The result for 1 and 2 month showed spotted babylon fed with Bacillus S11 has growth in shell length and in body weight of were higher than those of control group and fresh fish significantly (p< 0.05). The result for 4 month all treatment groups indicated that growth in shell length, body weight and survival rate were not differences among the treatment. Feed conversion ratio of spotted babylon was significantly different (p<0.05). After 4 months feeding trials, spotted babylon were challenged by immersion of Vibrio harveyi suspension 10⁶ CFU/ml. within 96 hours. The results showed that spotted babylon fed diets with Bacillus S11 supplemented ratio 1:2 ,1:5 and 1:10 survived 100%, 100% and 96.67%, respectively whereas the groups fed control diet and fresh fish has survival rate 66.67% and 70% was significant differences (p<0.05).