This study aimed to evaluate the effect of different feeding levels on productive performance of growing buffalo heifers. Eighteen growing buffalo heifers (156 ±… days old and 110 ±… kg live body weight) were allocated randomly and equally to one of three treatments of 6 heads per each. Animals received their feeding allowance according to Kearl (1982) and the experiment was ended when the heifers reached to the first services: R1, 100% of the feeding allowances during the whole experimental period (control); R2, 80% of the feeding allowances to 300 kg body weight, then followed by 100% till the end of the experiment; and R3, 80% of the feeding allowances during the whole experimental period. Digestibility trials were conducted to determine the feeding values of the experimental rations. Results indicated that treatments (R2 and R3) during the first phase recorded the lowest values of digestibility coefficients, feeding values, total body weight gain and daily gain than those fed on control diet. When the heifers in (R2) received 100% during the second phase, an improvement in heifers performance were observed in comparison with those in R3 treatment that recorded the longest periods (P<0.05) of  age at puberty and 1^st service compared to those in other treatments. Increasing the feeding level was significantly (P<0.05) affected of the all blood serum parameters. Total feed cost and return economic efficiency indicted that the animals fed R2 ration had the superior economic efficiency, followed by those in R3 and then R1 was ranked the last. It could be concluded that feeding the weaned buffalo heifers on 80% of their feeding allowances until 300 kg body weight, followed by 100% of the allowances was more beneficial for the productive and reproductive performance and economical efficiency of growing buffalo heifers under Egyptian condition.