The present study was conducted to evaluate the effect oforganic acids (citric, lactic and propionic) and their mixtures on carcass traits and blood biochemistry of broiler chickens. A total number of 480 broiler chicks (Ross) one-day old, nearly similar in live body weight were used in this study. Chicks were randomly divided into eight experiment groups each of 60 chicks in3 replicates of birds. Chicks of the first group fed starter and grower basal diets without any supplementation and considered as a control group, the second, third and fourth groups were fed starter and grower basal diets with 5g/kg of either citric, propionic or lactic acids, respectively. While, the fifth group fed starter and grower basal diets with 5g/kg citric acid and 5g/kg propionic acid. The 6^th and 7^th groups fed starter and grower basal diets supplemented with 5g/kg citric and 5g/kg lactic acids, 5g/kg propionic and 5g/kg lactic .The 8^th group fed starter and grower basal diets supplemented with 5g/kg of each of Citric+ Propionic+ Lactic. Results obtained showed that chicks fed diet supplemented with citric and lactic acid, respectively had significantly increased the absolute and relative weights of carcass and total edible parts, the highest averages of plasma total protein , globulin and decreased plasma AST and ALT. Chicks fed on diet supplemented with the mixtures of Citric + Lactic + Propionic acid showed the highest averages of absolute and relative weights of carcass and total edible parts, plasma total protein, globulin and lowest plasma creatinine compared with the other treatments and control group. While chicks received diet supplemented with citric acid showed the highest value of plasma albumin and relative economical efficiency (REE). Generally, it is clearly observed from this study that using organics and their mixtures had improved the carcass yield, blood biochemistry and economical efficiency of broiler chickens compared with control. Citric acid at a level of 5g/kg diet seemed to be adequate to achieve the favorable results and is being recommended from the economic point of view.