This study was investigated growth indices, survival, and health parameters of Litopenaeus vannamei of 8.64±0.31gr, fed different diets 0, 0.5, 1, and 2% of powder garlic for 60 days. Results showed that weight, length and specific growth rate (SGR) of shrimp fed diets containing 2% of garlic powder (15.42gr, 16.2cm and 1.27%, respectively) significantly higher than other treatments (p<0.05), however, due to a significant increase feed conversion efficiency (FCE) in this treatment, the feed conversion ratio (FCR) is significantly reduced compared to other treatments (p<0.05). Also, because of stimulation of immune system, total haemocyte count (THC) and total plasma protein (TPP) were significantly increased (p<0.05) compared to other treatment, which leads to significantly increased survival rate of shrimp fed diets containing 2% garlic powder compared to shrimp fed diets containing 0.5 and 0% of garlic powder (p<0.05). According to these results adding 2% garlic powder to the diet of L. vannamei will lead to improving growth indices and increase non-specific immune system efficiency.