The purpose of this study was to provide sufficient essential amino acids and to reduce dietary protein levels to an undesirable effect on carcass quality and to investigate the effect of different levels of protein on carcass composition to provide a diet with lower protein levels and more economical feed to poultry. 150 one-day-old broilers were divided into three groups for high protein, medium protein and low protein. During the period, weight gain of chickens and total feed intake of each group were evaluated. Water retention, brittle measurement, post-freezing dripping loss, dry matter or moisture content, mineral or ash measurement, lipid measurement and carcass protein measurement were studied and the data were analyzed statistically. Results show that there was a significant difference in the weight gain of the chicks on a weekly basis in the first, second, third, fifth and sixth weeks, and the high protein group had better weight gain. In this research, we tried to study the changes in carcass composition and growth efficiency by providing essential amino acids such as methionine and lysine and decreasing the protein level.