The goal of this study was to see how adding Nigella sativa (NE) and curcumin extracts (CE) separately and in combination affected broiler performance, blood biochemical markers, antioxidant status and intestinal microbiota. Four experimental diets formulated: Control, NE (600 ppm), CE (600 ppm), and mix (300 ppm NE + 300 ppm CE). A total 240 chicks at 11 days of age were assigned to the four dietary treatments of 60 chicks each. The results showed that the addition of NE, CE or mix to the broiler diets significantly enhanced (P<0.05) body weight gain and feed conversion ratio compared with control group. No significant differences (P>0.05) recorded for feed consumption among all treatments in all periods. The inclusion of NE or Mix significantly enhanced the levels of total protein and globulin. The addition of NE, CE, or the Mix did not impact urea, alkaline phosphatase, alanine transaminase, or aspartate aminotransferase levels (P>0.05), indicating that there was no deleterious effect on the liver or kidney function. Addition of NE and/or CE significantly (P<0.05) increased total antioxidant capacity and catalase while the level of Malondialdehyde decreased compared with the control. Addition of Mix increased (P<0.05) the triiodothyronine (T3) levels while not altered on the thyroxine (T4) and T4/T3 levels. The addition of NE or Mix increased the number of lactobacilli, and on the contrary, this addition reduced the total number of faecal bacterial and eliminated Salmonella sp. compared to the control. The results also exhibit that, CE was less efficient than NE extract in improving intestinal health, illustrated by the detection of pathogenic Salmonella sp. count. From these results, it could be concluded that adding NE extract alone or with the CE at 600 ppm revealed positive effects on the productive performance, economic efficiency, blood biochemical parameters, antioxidants status and intestinal microbiota of growing broilers.