18 Awassi lambs aged ranged from 3.5 - 4 months with an average weight of 23,67 ± 0,34 kg ,were used in this study, The lambs were chose randomly from sheep flock at Al-Rasheidia station, Mosul and was divided to three groups equal, fed for ninety days, the three groups on the same basal ration and supplemented with 1.5 and 3 ml garlic oil /animal / day for lambs in second and third groups respectively, while first group was left as control without supplementation , and study the effect garlic oil on production performances (average total gain, final weight , feed conversion and on some hematological & biochemical parameters . The results indicated that the second and third groups significantly (P≤0.05) increased in total gain , final weight , feed conversion ratio , hemoglobin , red & white blood cell count, while cholesterol , triglycerides were decreased significantly (P≤0.05) in the second and third groups ,respectively as compared to first group . On the other hand the periods has significantly (P≤0.05) affect on total gain and the final weight.