Twenty four Friesian male calves with an average body weight of 265 kg and 12 months age were used in this study. Calves were divided into four similar groups, assigned randomly to four experimental rations. Rations were formulated to be Isonllrogenous and had two different energy levels (70 or 60% TON). within each energy level two different levels of intake (ad-lib or 85% from the ad. lib. level) were given. Com silage and berseem hey were used as a roughage portion in all rations.Rations were offered to animal's groups by using the TMR feeding system. Oigestion coefficients of all nutrients were significantly (P<0.05) higher for 70%·TON ration than 60%-TON ration. Both TON and OCP were signiflcantly higherwith high energy rations compared with those of low energy ones. Intakes of OM. TON and OCP were significantly (P<0.05) higher with low than high energy rations. Final LBW showed marXed improvement by increasing level of dietary energy and feed intake, but the difference .••.. :(e not significant between ad.lib. and restricted levels for the same TON level, and between high energy-restrlcted and low energy-ad-lib. rations. The high- energy rations, regardless to level of feed intake. achieved more efficient feed utilization and better feed conversion than the low-energy rations in terms of OM. TON and DCP. Feeding 85% of ad-fib. caused an improvement in feed efficiency under the two levels of energy, but the differences were not statistically significant. Increasing the level of dietary energy and feed Intake decreased (P<0.05) pH values and concentration of NH3-N. and increased (P< 0.05) TVFAs concentrations at all sampling times. The ad-lib. level had higher (P< 0.05) TVFA's concentration than the restricted feeding level (85%). Concentration of total protein, albumin. glucose and activity of GOT and GPT in plasma increased (P<0.05) and concentration of cholesterol decrease (P<0.05) by increasing level of energy or feed Intake. The highest economic efficiency (169%) was obtained for calves fed 85% of ad.lib.high energy ration.