The objective of this study was to evaluate the impact of feeding protected Methionine on body weight, testicular parameters, semen characteristics and testosterone hormone in growing Awassi ram lambs. Ten mal Awassi lambs, weighing 34 kg ± 0.5 kg, age 8 month, were randomly allotted into two groups of equal number, fist was control group(c) and the second was treatment group (T). Lambs fed concentrated ration which contained barely seeds, wheat brand, soybean meal, urea, salt, limestone and wheat straw as a roughage ration. Lams in T group fed the basal control ration with 5% rumen protected methionine/ head / day. Testicular parameters was recorded. Semen collected by electric ejaculator and volume, sperm motility, sperm concentration, live and dead sperms and sperm abnormalities were evaluated. The results showed a significant (p≤0.05) increase in live body weight reached 47 kg ± 0.509 kg in treatment group than 40.4 kg ± 1.326 kg, protected methionine had no effect on testicular parameters in the first and second months of experiment but it had a significant effect in the third month of experiment. No significant effect of protected methionine supplementation on fresh semen characteristics (Semen ejaculated volume, semen concentration, mass and individual motility) but alive sperm ratio increased and dead sperms decreased significantly (P≤0.05) in treatment group than control in last month of experiment. Testosterone concentration was significantly (P≤0.05) increased in the second and third month in treatment group than control. The dietary supplementation with protected methionine showed a significant effect on body weight, Testosterone level and slightly effective on testicular parameters, semen characteristics of Awassi ram lambs.