This study investigated the impacts of dietary Moringa Oleifera leaves (MOL) and yeast culture (YC) (Saccharomyces cerevisiae) supplementation on nutrient digestibility, feeding value and rumen fermentation in sheep. Four digestibility trials were carried out using four healthy mature Saidi rams were used for each trail as 4x4 Latin square. Each trial lasted for three weeks, the first two weeks were considered as a preliminary period followed by one week collection period. The groups were a control group fed basal diet without supplement and treated groups fed MO,2.5% of  concentrate mixture (T1),  YC, 0.5% of  concentrate mixture (T2) and  2.5%  MOL  + 0.5% YC of concentrate mixture  (T3). All of Moringa leaves or yeast culture (YC) was mixed with concentrate diet. All animals were fed 60% of their requirements as DM, concentrate mixture while, wheat straw was given as roughages ad libitum. The experimental design was Latin square model. The data were statistically analyzed using general linear model (G.L.M) procedure of S.A.S (2001) program, version 8.2. The results referred that, the digestibility of dry matter, organic matter, crude protein, crude fibre and ether extract were improved (P<0.05) for T3 diet compared with control diet. However, no significant differences were found between T1 and T2 diets or between T2 and T3 diets. Also, the feeding value expressed as total digestible nutrient (TDN), digestible crude protein (DCP) and digestible energy (DE) were higher for T2 and T3 diets than T1 and control diets.No significant differences were observed in ruminal pH among groups. Supplementation of Moringa leaves with live yeast culture to concentrate diet (T3) increased (P <0.05) rumen ammonia nitrogen as compared with other groups. However, the volatile fatty acids (VFAs) was higher (P<0.05) with supplement YC to concentrate diet group (T2) than other groups. The total bacteria count in rumen liquid was higher (P<0.05) in yeast group (T2) than other groups. Also, all treated groups were higher in total bacteria count than control one. In conclusion, dietary supplementation of Moringa leaves and live yeast culture (S. cerevisiae) to concentrate mixture may improve nutrient digestibility and rumen fermentation patterns in sheep