Aim of this study was to evaluate the effect of inclusion dried leftover food (DLF) in the ration of crossbred calves (Balady x Friesian), on their growth performance, rumen function and blood parameters through a comparative feeding trial. Fifteen male crossbred calves (258±1 kg), were randomly assigned into three similar groups (five in each) and fed the tested rations for 16 weeks, as an experimental period. The tested rations were formulated from concentrate feed mixture (CFM) that partially substituted by 0, 20 and 40% of DLF for CFM1, CFM2 and CFM3, respectively, plus bagasse as a roughage portion for formulate the experimental rations R1 (control), R2 and R3 as tested one, respectively. Results showed that most nutrient digestibility coefficients and feeding values were improved with the higher level of DLF (40%) in ration, than R2 and R1 (control). NH3-N and pH values in rumen liquor were decreased with increasing the level of DLF up to 40% (R3) in rations. The vice versa trend was found among dietary treatments respecting TVFA´s concentrations in the rumen. Insignificant differences among tested rations in respect of most blood metabolites were found. Total body weight gain and daily gain were significantly higher only with (R3) than those of R1 (control). Economic efficiency was improved by feeding ration that contained 40% DLF (R3) in comparison with R1. This study concluded that considerably to use dry leftover food up to 40% level could be recommended for formulation the rations of crossbred cow calves.