In this study, we investigated the effect of Moringa oleifera leaves (MOL) supplements on the performance, ileal microbiota carcass traits and biochemical and antioxidant parameters of broiler chickens. MOL was added to starter, grower and finisher diets at four levels (0%, 0.5%, 1.0% and 5.0%). A total of 320 one‐day‐old mixed‐sex Cobb‐500 broiler chicks were divided equally into four treatment groups, with 5 replicates of 16 chicks each until 42 days of age. Compared to the control group, chicks fed 0.5% and 1% MOL exhibited a higher final body weight (FBW), greater weight gain (BWG), and better average daily gain (ADG). Feed intake (FI) gradually decreased as the inclusion rate of MOL in the broilers' diet increased to 5%. The best feed conversion ratio (FCR), protein efficiency ratio (PER) and performance index (PI) were observed in broilers that were fed the MOL diet. The percentage of abdominal fat in broilers decreased significantly in response to dietary supplementation with MOL. The haematological profile in the MOL group revealed a lower WBC count and lymphocyte percentage but higher heterophil and H/L ratio without affecting haemoglobin and RBC count. The inclusion of MOL increased total serum protein, Ca and P levels but decreased glucose, cholesterol, triglycerides, AST and ALT concentrations. Moreover, dietary MOL increased the activities of GSH, CAT and SOD, GPx and GST while decreasing the TBARS level. The pH value decreased in the ileum of broilers fed the 1% and 5% MOL diet compared to the other treatments. Decreased ileal counts of E. coli, Salmonella and Staphylococcus spp. were observed whereas the total ileal Lactobacillus spp. count increased in broilers fed the MOL diet. In conclusion, the MOL supplement can enhance growth performance and antioxidant status, alter ileal microbiota and protect against enteropathogens with no deleterious effects on the broiler chickens.