A study conducted at poultry field/Animal Production Department/College of Agriculture, Kirkuk University, Iraq. The experiment aimed to study the effect of adding Moringa oleifera leaf powder with or without probiotic on growth performnce, carcass characteristics and some biochemical blood characteristics for broiler. 288 chicks of Ross 308 broilers (unsexed) were bred from one-day old until 42 days, and the average weight for chicks were 41.9 g. The chicks were randomly distributed to 6 treatments, with 4 replicates each treatment, (12chicks/replicate). The experimental treatments include: - T1: control, T2: standard diet + addition of probiotic 3 g/kg feed, T3: addition of Moringa oleifera leaf powder 2.5 g/kg feed, T4: addition of Moringa oleifera leaf powder 5 g/kg feed, T5: addition of Moringa oleifra leaf powder 2.5 g/kg feed + probiotic 3 g/kg feed and T6: addition of Moringa oleifera leaf powder 5 g/kg feed + probiotic 3 g/kg feed. The results showed a significant increase (P<0.05) in T5 in live body weight, weight gain rate and feed intake rate compared with other treatments. The feed conversion ratio was significantly improved in T4 and T5 compared to the other treatments. The average empty carcass weight was significantly increased in T4 compared to the other treatments, and the results also showed that the pieces (breast and thigh) and (wing, neck and back) were not affected by the study parameters. The relative weight of the liver and heart recorded a significant value in T2 compared to the other treatments. T3, T5 and T6 had a significant effect on the relative weight of gizzard, but the relative weight of abdominal fat was the lowest in T3 and T5. A significant decrease was found in the total protein concentration of T6 compared to the rest of the treatments, and there was a significant superiority of T4 and T5 compared to the other treatments in the concentration of glucose, and the total cholesterol concentration which was lower in T1, T3 and T5 compared to the rest of the treatments. The concentration of triglycerides decreased in T3 and T5, and T3 recorded the lowest concentration in uric acid compared to the rest of the treatments.