The research was conducted to examine the effects of supplementation of alfalfa and rosemary extracts on performance and serum composition of broiler chickens. A total of 300 broiler chickens were divided into 4 groups and 3 repetitions with 25 chicken each.G1, First group as control group did not receive any herbal planet extract, G2) 200 ppm of alfalfa extract, G3) 200 ppm of rosemary extract, G4) 200 ppm of both herbal planet. The results showed that using these medicinal plant extracts in their diet had significant effects on performance, carcass traits and blood biochemical parameters of broilers (p<0.05). The highest amount of daily feed intake and body weight gain was observed in the group 2 and the highest percent of liver was observed in experimental group 3, the highest percent of breast and lowest percent of abdominal fat was in experimental group 4. Also the serum total cholesterol, Triglycerides and LDL concentration were significantly reduced in groups of 4 compared to the control group (P<0.05).
