A total of 60 unsexed day old broiler chicks of (Ross 308) were divided into 2 groups, each of 30 chicks were  housed in a separate individual pens, during the period 1^st/10 till 5^th/11 2012, for 5 weeks. Effective Microorganisms (EM) was administered at a rate of 10 ml/liter of drinking water. Chicks were vaccinated against Newcastle disease (ND) (Lasota strain). Blood samples were collected and divided into two parts, one for estimation of trace elements (copper, zinc, cobalt and manganese) using Atomic absorption, while the other part for estimation of antibody titers against Newcastle disease virus. Results showed that there was a significant (p˂0.05) increase in the antibody titers against Newcastle disease virus vaccine of 5347.07±117.03, in chicks amended with EM when compared with the control group of 2949.24±314.51. There was also a significant (p˂0.05) increase in the mean of trace elements of Zn, Co, Cu and Mn which are (1.171 µg/ml, 6.128 µg/ml, 0.376 µg/ml and 0.146 µg/ml)in treated chicks with EM, in comparison with  (0.587 µg/ml, 4.151 µg/ml, 0.232 µg/ml and 0.000) respectively in the control group.