Forty-eight Mehraban male lambs each of 6 months of age and 32.1 ± 3.9 kg Body Weight (BW) were utilized to study the effects of administration of Echum amoenum Extract (EAE) on plasma metabolites and Methane gas. Following 2 weeks of adaptation and being fed a Total Mixed Ration (TMR) of 60 to 40-ratio concentrate to forage, the lambs were divided by their initial BW into 4 groups of 12 lambs each in a completely randomized design. The control group received only TMR, while the second, third and fourth groups receiving 0.3 , 1.5 or 3 ml/Kg DM EAE extract for a 90 day experimental period. The Echum amoenum extracts were added to the diet fed to each lamb at the 8:00 h. Blood samples were collected at day 37 (S1) and day 72 (S2) from the jugular vein. The plasma metabolites studied were total protein, albumin, creatinine, Blood Urea Nitrogen (BUN), glucose, triglyceride as well as cholesterol. The correlation among, and between these metabolites, was also assessed. The results indicated that creatinine, BUN and triglyceride were significantly different from control in day 37 of sampling.