The aim of this study was to determine the effects of dietary supplementation with effective microorganisms (EM) on the growth performance and some blood parameters in turkey poults. A total of 180 unsexed poults of the Bronze turkeys strain at age of 2 wk was randomly divided into five groups with three replicates (12 in each). Birds in the 1^st group (G1) were fed basal diet without additives (control), while those in the 2^nd, 3^rd and 4^th groups were fed the same diets supplemented with EM at levels of 5, 10 and 15 ml/kg diet, respectively. Birds in the 5^th group were fed the same diets supplemented with Lincomycin (2 g/kg diet). Live body weight (LBW), averages of daily gain (ADG) and feed intake (ADFI) and feed conversion ratio (FCR) were recorded at 2, 4, 8 and 12 wk of age. At the end of experimental period (12 wk of age), blood samples were taken to evaluate some hematological parameters including count of red (RBCs) and white (WBCs) blood cells as well as hemoglobin (Hb) concentration. Economic feed efficiency (EFE) was calculated. Results showed beneficial effects of adding 15 ml EM (G4) or 2 g Lincomycin per kg diet on LBW of poults, being the heaviest (P≤0.05) in G4 and G5. ADG was the highest (P≤0.05) in G4 and G5 as compared to control (G1) and other groups (G2 and G3) at 4-8, 8-12 and 2-12 wk of age. ADFI was higher (P≤0.05) in all treatment groups (G2-G5) than in G1 at the interval from 2 to 4 wk of age.  ADFI was the highest in G2 and the lowest in G3 at other intervals and during the whole feeding period (P≤0.05). FCR at 2-4 wk of age was better (P≤0.05) in G4 and G5 than in G1. At 4-8, 8-12 or 2-12 wk of age, FCR was higher (P≤0.05) in G3, G4 and G5 than in G1 and G2, being the best (P≤0.05) in G5 and the poorest in G1. WBCs Count was higher (P≤0.05) in G4, and lower in G3 than in G1. but did not differ in G2, G5 from that in G1. RBCs Count and Hb concentration decreased (P≤0.05) only in G5. From the economic point of view, birds in G4 showed the highest EFE relative to control group (148%). In conclusion, using effective microorganisms (15 ml EM/kg diet) instead of antibiotics (2 g Licomycin/kg diet) as growth promoters in diet of poults during the growing period (2-12 weeks of age) had beneficial effects on growth performance, healthy status and economic feed efficiency.