An experiment was carried out to determine the effect of adding dietary supplementation (FLORAC^®) which contains several organic acids and Bacillus cereus var toyoi as Probiotic compounds on the blood parameters of sixteen Arabian horses (male only). The horses were distributed in two equal groups, experimental and control groups. All horses were housed for one week on same conditions without adding FLORAC^®, then FLORAC^® was added to the diet of the experimental group with dose of 3g\kg feed for eight weeks. The blood samples were collected and analyzed every two weeks. Over time, we observed that the average of the count of RBCs and the concentration of Hb was increased with significant differences (P<0.05) compared with the control group. There were no significance (P>0.05) in the number of WBC in both groups. Additionally, there was a slight decrease in the values of the studied enzymes (ALT, AST, CK), but they remained at their normal values over time, and there were no significant differences in comparison to the control group (P>0.05).