Ptecticus tenebriferwas incorporated to partially or totally replace the diets of juvenile white shrimp (Litopenaeus vannamei). Experimental groups of shrimp with an average initial body weight of 0.014 ± 0.001 g were fed each of the 5 diets formulated to include 0, 25, 50, 75, and 100% (C, T25, T50, T75, and T100, respectively) of Ptecticus tenebriferpowder substituted for commercial feed. After eight weeks of feeding trials, juvenile shrimp fed with diets T25 and T50 showed higher live weight gain (2.298 ± 0.405 and 2.539 ± 0.406, respectively), and a better feed conversion ratio (1.389 ± 0.246 and 1.536 ± 0.246, respectively) compared to those of shrimp fed a control diet. Survival rate was 98% in all experimental groups except for the T75 group (66.67±57.73% survival). The levels of immune markers such as beta-glucan binding protein, prophenoloxidase, and crustin associated with the cellular and humoral immunity of shrimp were found to be higher in 25% and 50% commercial feed replacement groups. A reduction in total nitrogen, nitrite nitrogen, and ammonia levels was greater in T25 and T50 rather than in T75 and T100. These results clearly indicate that replacement of feed with 25 to 50% Ptecticus tenebriferpowder in juvenile white shrimp diet was optimal in promoting the growth performance of shrimp without any adverse effects.