Abstract: Objective: This study aimed to evaluate the effect of feeding different levels of dry Moringa oleifera leaves (DMOL) on nutrient digestibility, some blood constituents and performance of suckling buffalo calves. Materials and Methods: Thirty newborn buffalo calves were used in feeding trial through suckling period. Calves were suckled buffalo milk and fed calf starter and berseem hay ad libitum as control ration, while in the other tested rations 5, 10, 15 and 20% of calf starter was replaced by DMOL for R2, R3, R4 and R5, respectively. Results: Data indicated that, DMOL contained 28.00% Crude Protein (CP), 6.23% Ether Extract (EE), 15.39% Crude Fiber (CF), 41.95% NFE and 8.43% ash (on DM basis). Nutrient digestibility, nutritive values, weight gain, feed conversion and economic efficiency of tested ration were significantly (p<0.05) increased with increasing the level of DMOL in the rations up to 15% and decreased afterwards at 20% level, which was nearly similar to control ration. There were insignificant differences in blood total protein, globulin, creatinine and alanine aminotransferase (ALT) among experimental rations. While, values of albumin, urea and aspartate aminotransferase (AST) were significantly (p<0.05) different among tested rations. Conclusion: Results of the present study concluded that replacing up to 15% of calf starter by DMOL improved growth performance of suckling buffalo calves, if compared with replacing 20% and control group.