Four isonitrogenous and isocaloric diets (30.22 ± 0.02% CP and 19.007 ± 0.015 MJ kg-1 diet) were formulated to represent four dietary treatments. The first treatment (control) without poultry by-product (PM0), while the second, third and fourth diets formulated with substitution of fish meal by poultry by-product meal as 50, 75 and 100%, respectively. Each diet was fed to 100 juvenile tilapia (1.5 ± 0.05 g), in triplicate cement ponds of 2 m3. Fish were fed diets at a rate of 3% of its biomass daily divided into two equal portions. The highest (P<0.05) growth performance parameters (finial weight, weight gain, daily gain and specific growth rate) and best nutrient utilization (feed conversion ratio, protein efficiency ratio and net protein utilization) were recorded with PBM0 and PBM100% groups. The applied treatments showed insignificant effects on nutrients digestibility coefficient among dietary groups for Dry matter, Energy, CP, Fat and nitrogen free extract. No significant effects on dry matter, crude protein, fat and ash contents were recorded between dietary treatments. Juvenile tilapia fed the experimental diets showed insignificant different in blood contents (P<0.05) between groups. The present study recommended substitution of 100% fish meal with poultry by-product meal in juvenile Nile tilapia diets.