The present study investigated the effects of different levels of methionine and dietary electrolyte balance and interaction of these two factors on the performance traits of the immune responses in broiler chickens. In this study 360 one day old Ross 308 male broiler chickens were examined which considered four replicates for each experimental treatment with ten chickens per replicate. Dietary treatments were examined in a 3*3 factorial experiment based on a completely randomized design consisted of three levels of methionine (100,110 and 120% which recommended by the National Research Committee) and three levels of dietary electrolyte balance (150, 250 and 350 mEq/kg) during the starter (1-21 days) and grower phase (22-42 days). Results showed that the utilization of methionine levels caused significant differences (p 0.05) on the average total feed intake, also utilization levels of electrolyte balance caused significant difference (p 0.01) on average daily feed intake, average daily weight and feed conversion ratio during grower and total period. The interaction between these two factors showed significant differences (p 0.05) on the total period average daily feed intake and the grower period feed conversion ratio. In this study the utilization of methionine levels a significant effect (p 0.01) on serum albumin, globulin and albumin ratio to total serum globulin while electrolyte balance levels and interactions effects of these factors did not cause a significance difference. There was a significance difference (p 0.01) by using of the levels of electrolyte balance on the villi height but it did not observe any effect on the crypt depth and villi height to crypt depth ratio, also, using of different levels of methionine and interaction effects of these two factors did not cause any significant effect on the histological characteristics of intestine. In addition, the findings showed that there were not significance effects with utilization of different levels of methionine, electrolyte balance and interaction effects of these two factors on the antibody titer against SRBC. There were not any significance different among the methionine levels, electrolyte balance and interaction effects of these two factors on the partial of blood leukocyte count. Results of this study showed the utilization different levels of methionine didn't cause significant difference in relative weight (spleen, bursa and abdominal fat), while it had a significant effect (p 0.05) on the relative weight of pancrease and a significant effect (p 0.001) on the relative weight of the total intestine. Although a statistically difference didn't observe by using the different levels of methionine on the relative weight of abdominal fat, a numerically rate of abdominal fat decreased by increasing the levels of methionine. Also utilization of the electrolyte balance levels cause significant difference (p 0.001) on the relative weight of abdominal fat, but interaction effects between these two factors showed no significant effects on carcass traits.