The number and species of Vibrio spp. bacteria that may be present in normal healthy Penaeus vannamei juveniles are described. The hepatopancreas, stomach, intestine and haemolymph of P. vannamei juveniles were sampled. All three areas of the digestive tract contained a diverse population of Vibrio spp. but the haemolymph contained bacteria in only 14.3% of the animals sampled, with counts of Vibrio spp. ranging from 2×10² to 3×10³ CFU/ml. The Vibrio spp. isolated from the digestive tract included both sucrose and non-sucrose fermentors whereas the haemolymph contained only non-sucrose fermentors. The findings of this study would suggest that there may be a wide range of Vibrio spp. in the hepatopancreas of normal healthy P. vannamei.