Western White Shrimp (Litopenaeus vannamei) is recognized as one of the most important aquaculture species. Improving growth performance and immunity in this species faces several challenges. The use of bile acid supplements as dietary additives can enhance shrimp growth, survival, and immune responses. This study aimed to investigate the effects of adding various levels of bile acids on growth performance, immune indices, and the expression of immune-related genes in Western white shrimp (L. vannamei). In this research, 300 shrimp with an average weight of 6 ± 0.2 grams were randomly placed in 15 tanks with five treatments and three replications. Treatments included a control group (without bile acid supplement) and four treatments with different levels of bile acids (0.1, 0.2, 0.4, and 0.6 grams per kilogram of feed). Results indicated no significant differences in initial weight, final weight, weight gain, and feed conversion ratio among the control group and treatments with 100, 200, 400, and 600 mg/kg bile acids (P > 0.05). However, survival rate was significantly higher in the 100 mg/kg treatment compared to the control and other treatments (P < 0.05). Regarding total hemocyte counts, significant differences were found between the control group and treatments with 200, 400, and 600 mg/kg (P < 0.05), but not with the 100 mg/kg treatment (P > 0.05). The study further revealed significant differences in total hemocyte counts, as well as in hemocyte subtypes (hyaline, granular, and semi-granular), between the control and all treatments, except between the 400 and 600 mg/kg treatments and between the 100, 200, and 600 mg/kg treatments (P > 0.05). Additionally, the expression of immune-related genes showed that the expression of prophenol oxidase was highest in shrimp fed with 400 mg/kg bile acids, while the control group showed the lowest levels. The expression of Pen3a was significantly higher in the 400 and 600 mg/kg treatments compared to the control (P < 0.05),