This study aimed to assess the effect of prebiotics (dry yeast) and folacin (folic acid) on oxidative stress, performance parameters, and blood characteristics in Japanese quails. One-week-old, 180 sexed chicks were randomly distributed into 5 groups with 4 replicates (two replicates/sex). Birds were divided into 5 treatments: 1st – control basal diet (BD); 2nd – H2O2 1% in drinking water; 3rd – H2O2 + folic acid (F) 5 mg/L in drinking water; 4th – H2O2 + yeast (Y) 10% in a basal diet; and 5th – H2O2+F+Y. The results showed that hydrogen peroxide treatment caused a notable decrease in the body weight of both sexes, as well as in the relative weights of the female organs, while the weight of some of the male organs increased compared with the control, and all treatments with H2O2 caused an increase in the relative weights and the live body weight compared with the peroxide treatment. The peroxide treatment led to a significant decrease in the hematological parameters of both sexes in comparison with the control group, whereas all treatments improved the blood levels compared with the peroxide treatment. The biochemical parameters of both sexes increased with the administration of hydrogen peroxide, particularly at the MDA level, but they improved and returned to the normal condition in the various treatments with H2O2, especially in the levels of GSH as opposed to the peroxide treatment. These results indicate that the administration of yeast or folic acid alone or in combination reduces the harmful effects of oxidative stress and improves performance