This study was conducted to investigate the chemical composition, digestibility, nutritive value, nitrogen retention, growth performance, economical efficiency and blood constituents of lambs fed SBLS treated as compared with different urea levels with CFM plus WS. Eighteen growing Frafra male lambs with 20.730 ± 0.29 kg average LBW and six months of age were used in the feeding experiment. TI, lambs were fed CFM +WS as control, T2, lambs were fed CFM + SBLS supplemented with 0.3% urea, T3, lambs were fed CFM + SBLS supplemented with 0.6% urea. Digestibility and nutritive values of compared with ureated SBLS. Ureated diets showed significantly higher (P<0.00l) values for nitrogen retention compared with control group (TI). Growth performance was shored significantly (p<0.001) by increasing levels of treated SBLS in diets. Feed consumption and feed conversion ratio decreased significantly (p<0.001), lambs fed T2 and T3 showed the best feed conversion ratio as kg DM and kg TDN kg/kg gain compared with those fed control. Consequently, lamb's fed ureated SBLS recorded lowest feed cost (LE), (better efficiency) compared with those fed the control diet. Results of blood constituents as GL, TP, T3 and T4 were increased by adding SBLS in sheep diets and differences were significant (p<0.001) while the rest of constituents such as (AL, Gb, urea, cholesterol, Tr, ALT and AST) were not differ significantly by (P<0.05).