The present study aimed to investigate effects of adding some probiotics as Bacillus subtilis (B. subtilis) and Saccharomyces cerevisiae (S. cerevisiae) on the growth performance, blood biochemical parameters, and specific activity of some digestive enzymes as (trypsin, chymotrypsin and α amylase). A total of 150 Japanese quail chicks were randomly distributed into three groups. The first group (control group) received the basal diet that contains recommended requirements; the second group received the basal diet with (1×108 CFU /kg DM Bacillus subtilis) and the third group received the basal diet with (3×108 CFU /kg DM Saccharomyces cerevisiae). There was a significant improvement (p<0.05) in body weight gain, feed conversion ratio (FCR) and specific growth rate (SGR) in the group supplemented with Bacillus subtilis and Saccharomyces cerevisiae when compared with the control group, while feed consumption not affected among groups. Serum cholesterol, low density lipoprotein (LDL), high density lipoprotein (HDL) were significantly improved in the second group, while triglycerides slightly increased in this group. The addition of Bacillus subtilis and Saccharomyces cerevisiae significantly decreased the serum creatinine and urea levels (p<0.05) compared with the control group. All groups had no significant difference in serum total protein, albumin, and globulin. However, blood and aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels were significantly (p<0.05) decreased in the second group. Bacillus subtilis and Saccharomyces cerevisiae improved digestive enzymes activity especially α amylase enzyme. It is recommended to add these additives during quails fattening, as they could improve birds' health and production.