The variations of duodeno-jejunal bacterial flora are evaluated. 26 celiac children aged 2 to 7 years were divided in three groups. First group: 8 children in active phase of disease on a free diet; Second group: 10 children kept since one year on a gluten-free diet; Third group: 8 children challenged with gluten for some months. As the same time of the jejunal biopsy, a sample of duodenal juice was obtained for bacteriological examination; for this purpose were used the following culture media: Fluid thioglycollate medium (FTM), Blood-agar, Bile Esculin Azide Agar (BEAA), SF, selective for enterococcus, and MacConkey Agar. The results are: The number of bacterias in the first and third group is significantly higher (p less than 0.001 and p less than 0.05 respectively) than the second group with normal intestinal mucosa. Particular variations in bacteriological species in the three groups are not demonstrated. The excessive growth of bacterias in active phase of celiac disease could worse the absorption of lipids, vitamins, iron, and others substances and it could facilitate the local inflammatory processes in the small intestine.