Turbot (Scophthalmus maximus) is an economically important marine fish species in northern China. With the unceasingly amplification of farming scale and great improvement of intensivism in recent years, turbot diseases have been occurring frequently. Bacillus cereus YB1 could be used as a candidate probiotic strain, which has animal safety for turbot at a certain concentration. The present study aimed to investigate the effect of B. cereus (YB1) on growth performance, liver immune enzyme activity, intestinal digestive enzyme activity, and intestinal tissue structure of juvenile S. maximus, and would provide new probiotic strains for turbot aquaculture. A total of 720 healthy juveniles with an average body weight of (3.6±0.7) g were randomly divided into 4 groups with 3 replicates per group and 60 fish per replicate. The fish in the 4 groups were fed diets containing YB1 at a viable count of 0 (control), 105, 106, and 107 CFU/g at (21±2)℃, respectively, and the experiment lasted for 50 days. Results showed that the weight gain rate (WGR) and specific growth rate (SGR) were significantly higher in juvenile turbot fed diet supplemented with 107 CFU/g of YB1 than those of the fish fed the control diet (P<0.05). The amount of protease and amylase increased by 57.86% and 82.37%, respectively in 106 CFU/g group, and were significantly higher than those in the control group (P<0.05). Lipase content of fish in 107 CFU/g was significantly higher than that of the control group (P<0.05). Catalase activity in fish fed diets supplemented with YB1 was not significantly different from fish in the control group. Malondialdehyde content of juveniles fed 106 CFU/g YB1 dietary supplement was decreased by 42.03%, and was significantly lower than that in the control group (P<0.05). SOD activity of fish fed YBI increased compared with that of the control, however, the increase was not significant (P>0.05). YB1 led to a significant increase in the height and number of folds in the intestinal mucosa of turbot (P<0.05). Intestinal muscularis thickness was significantly increased in the 106 CFU/g YB1 dietary supplement group than in the control group; it was 68.91% higher than that of the control group at the end of the experiment. In this study, B. cereus (YB1) could promote the growth of juvenile turbot, improve the activities of digestive and liver immune enzymes in their intestine, and improve the structure of intestine. This study shows that B. cereus (YB1) can be used in turbot aquaculture, with a recommended dosage of 106 CFU/g.