High prices of protein used in commercial feed in shrimp farming has led to a need to find alternative sources of protein to meet the nutritional requirements of shrimp. The aim was to evaluate different levels of replacement of fishmeal by Spirulina platensis (SP) in diets for post-larvae of marine shrimp. We use post-larvae with an average of 0.74 ± 0.11g were randomly divided into an aquarium with continuous aeration. Four diets were formulated with substitution levels of the protein of fish meal: R1 (0%), R2 (50%), R3 (75%), R4 (100%), and the control diet supplied with commercial feed supplied to the post larvae in four meals per day for 30 days. Were determined weight gain (WG), weight (FW), length (FL), feed conversion (CV) and survival (S). The results of each of the parameters of analysis of variance, with significance level of 5%, were compared with each other, which revealed no significant differences (p> 0.05) between the variables, indicating efficiency of Spirulina platensis in all diets. The parameter variance analysis for the zoo technical performance of shrimp fed experimental diets in the various treatments showed no significant effect on increasing substitution of fishmeal by the freeze-dried Spirulina platensis. While in a not significant, it is observed that the diets which present lower levels of fishmeal by the freeze-dried Spirulina provide the best results in the indexes of productive performance, showing that a reduction in the incorporation of fishmeal up to 50% by this microalgae is possible without affecting the final weight gain and the other parameters. This work showed to be possible use the Spirulina platensis like the alternative diets in Litopenaeus vannamei post-larvae reared because we can reduce the fish flour in the 50% without compromising performance parameters Shrimp.