A total of 360 IR broiler chickens used at hatch, weighed and partitioned into equal six experimental groups each of three replicates to investigate the effect of dietary probiotics (PB), citric acid salt (CA) and their mixture addition on productive and physiological parameters at fattening period . Chicks in first group fed experimental diets without any supplement as a control, second group fed diets supplemented with 0.05% PB, third and fourth groups fed diets supplemented with 0.25 and 0.50% CA, respectively, while fifth and sixth groups fed diets supplemented with mixture from PB and 0.25 or 0.50% CA, respectively during experimental period (at hatch up to42 day of age). The results indicated that growth performance traits not significantly influenced by PB and CA addition except for feed intake which significantly (P≤0.05) improved by 0.25% CA than the control. All nutrients digestibility were significantly improved with supplementing CA alone to the diets except for crude fiber. Chicks fed PB or CA and their combination had higher hemoglobin, red and white blood cells count and lymphocytes (L %) than the control, however, heterophils (%) and H/L ratio were significantly decreased. Serum cholesterol and triglycerides were insignificantly decreased by dietary treatments. Economic efficiency was improved for all treated groups than the control. So that, supplementing citric acid by 0.25% alone or in the combination with probiotic (0.05%) to broiler diets could be used to improve growth and physiological performance as well as economic efficiency during fattening period.