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The rapid expansion of commercial culture of penaeid shrimp is threatened by Vibriodiseases affecting survival and growth. These opportunistic microorganisms are considered part of the normal ecosystem of penaeid shrimp and cause diseases only under conditions that favor them over the host. Shrimp larvae show different susceptibility to these pathogenic agents. In the present work, we report on a comparative study of the susceptibility of all American white shrimp (Litopenaeus vannamei) larval substages to four potentially pathogenic Vibriospecies (V. harveyi, V. parahaemolyticus, V. alginolyticus,and V. penaeicida). Strains of these bacterial species were used to infect nauplii, protozoea I–III, mysis I–III, and postlarvae 1 by immersion challenge at 103, 105, or 107cfu mL−1for 30 min. V. alginolyticusinfection had no significant effect on survival rate, compared to control, in all shrimp larvae and at all doses tested. Shrimp larvae infected with V. alginolyticusshowed a high survival rate compared to other Vibriospecies at the three dose levels. V. penaeicidaproduced a significant mortality effect (P< 0.01) in all shrimp substages and only in postlarvae 1 at low infection dose (103cfu mL−1). V. harveyiand V. parahaemolyticusinduced significant mortality rates (P< 0.01) only at high doses in shrimp larvae. In summary, shrimp larvae demonstrated an age susceptibility that depends on the Vibriospecies and dose level.