The aim of the present study was to determine the effect of the addition of prebiotic Immunobeta and probiotic Zoovit on the biochemical parameters of blood in Ile-de-France lambs. The research was carried out at the Agricultural Institute - Stara Zagora. It includes a total of 45 Ile de France lambs, divided into three groups of 15 - one control and two experimental. The groups were formed by the method of analogues, equalized by live weight at the beginning of the experiment, type of birth and sex. The animals of the I experimental group received 8 g of the prebiotic Immunobeta individually once a day, and those of the II experimental group the same amount of prebiotic with the addition of 4 g of the Zoovit probiotic. Blood for the study of 8 animals from each group was taken at the beginning and at the end of the experiment. In the indicators of albumin, urea, glucose, cholesterol, creatinine and bilirubin, significant differences were reported after the addition of the prebiotic Immunobeta compared to those at the beginning of the trial. A significant decrease in albumin (P