The present study shows that the dietary protein level markedly affects the growth; feed utilization,and physiological status of Nile tilapa in all weight ciasseh. The optimum dietary protein required for Nile tilapia is weight dependant;fry tilapia(-0.5 g ) required the 45%-CP diet for optimal growth; whereas, fingerling (-20 g) and advancedjuvenile (-40g) performed optimally with the 35%-CP diet. EI-sayed and Teshima(1991) found similar results in terms of the protein requirement of Nile tilapia;with values ranging between 20% and 56%CP.