Abstract: This study was conducted to investigate the effect of different levels of coriander (Coriandrum sativum) seed powder, as a growth promoter in broiler chicken on performance, carcass yield and blood profile. A total 240 (Ross 308) one day-old broiler chicks were allocated randomly into four treatments of (60 chicks/ group). Each treatment had three replicates (20 chicks/ replicate) according to a completely randomized design (CRD) for 45 days. The chickens were fed on diets containing 0% (T1) as control, 1.5% (T2), 2.5% (T3) and 3.5% (T4) of coriander seed powder. The feed intake, live body weight and weight gain were weekly measured and blood samples were taken on 45th days of the trail for the determination of the percentage of white blood cells and to assess blood biochemical parameters. The results showed that there was no significant difference (P>0.05) in the performance. Moreover, the dressing percentage and edible giblets were not influenced by dietary supplements, while the highest of the carcass yield without skin were obtained when the broiler chicken fed a diet containing 1.5% coriander seed, however, the higher values of heart weights (P<0.05) were obtained at 2.5% as compared to control. In addition, the serum triglyceride was significantly reduced (P<0.05) at 1.5%, while the HDL was significantly increased (P<0.001) at level 1.5% of coriander as compared with the control and 3.5%group. The GOT and GPT were significantly increased at 3.5% as compared with the control and 1.5% group (P<0.01) and (P<0.05) respectively. The basophil and Eosinphil cell counts were significantly increased at 2.5% (P<0.05 and P<0.01) respectively, while the Lymphocyte was significantly increased at 1.5% (P<0.01). However, the Heterophil and H/L were significantly reduced at 1.5% (P<0.05). In the conclusion it appears that the best results of biochemical blood profile, immune response and dressing percentage without skin were obtained when the diet was supplemented with coriander at 1.5%. Key words: Coriander, broiler chicken, performance, blood parameter.