An experiment was conducted to study the effect of feeding diets comprise different levels of mungbean at expense of soybean meal protein on growth performance and carcass characteristics of Arbor-Acres broiler chicks from 0-7 weeks of age. Two hundreds and forty day-old broiler chicks were randomly divided into four experimental treatment groups with three replicates each. The different experimental diets (0, 20, 30, 40 % mungbean at expense of soybean meal protein) were maintained iso-nutritive. At the end of 28 days of age, weight gain and feed conversion values of chicks fed mungbean diets were approximately similar to those recorded by chicks fed control diet. At the end of experiment (7 weeks) the values of weight gain, feed conversion, protein and energy utilization, performance index and carcass characteristics of birds fed the mungbean diets had also no significant differences with those fed the control diet. It could be concluded that mungbean seeds could be used in broiler diets as promising source of plant protein up to 40% of soybean protein