Abstract: In order to further understand the germplasm characteristics of Mazhan red chicken and clarify the breeding direction, the slaughter performance（live weight, carcass weight, half-eviscerated weight, full evisceration weight, chest muscle weight, leg muscle weight, abdominal fat weight, slaughter rate, half-eviscerated rate, full evisceration rate, chest muscle rate, leg muscle rate, abdominal fat rate）, muscle quality（meat colorbrightness, redness and yellowness and shear force）, conventional nutrients（water content, crude protein, crude fat, calcium and phosphorus）, amino acids and fatty acids contents of 9-month-old Mazhan red roosters were tested. The essential amino acid evaluation was performed according to the equilibrium model of essential amino acids in human body and the whole egg protein amino acid model recommended by FAO/WHO（Food and Agriculture Organization of the United Nations/World Health Organization）. The results showed that the slaughter rate, half-eviscerated rate, full eviscerated rate, chest muscle rate, leg muscle rate, and abdominal fat rate of Mazhan red chicken were 90.75%, 83.69%, 65.47%, 16.65%, 33.77%, and 0.46%, respectively. The brightness, redness, yellowness, and shear force of pectoral muscle were 49.50,-0.23, 0.99, and 4.56 kg/f, respectively. The moisture content, crude protein content, crude fat content, calcium content, and phosphorus content of pectoral muscle were 70.68%, 22.01%, 3.16%, 36.94 mg/kg, and 674.15 mg/kg, respectively. Seventeen kinds of amino acids were detected in breast muscle, and the most abundant amino acid was glutamic acid, followed by lysine, leucine, aspartic acid, glycine and alanine. The proportions of essential amino acids, conditional essential amino acids, non-essential amino acids and delicious amino acids in the total amino acids were 42.70%, 21.20%, 36.10%, 36.83%, respectively. All amino acids were higher than the FAO/WHO protein standard model, except for valine and threonine, which were slightly lower than the model. All amino acids were lower than the model, except for leucine and lysine, which were higher than the whole egg protein standard model. Valine was the first limiting amino acid. The contents of saturated fatty acid, monounsaturated fatty acid and polyunsaturated fatty acid in pectoral muscle were 33.03%, 32.48% and 34.49%, respectively, and the ratio was 100∶98∶104. The results indicated that the slaughter rate and full evisceration rate of Mazhan red chicken were high, and the meat performance was good. The contents of glutamic acid, aspartic acid, glycine and alanine in pectoral muscle were high; the shear force was low; and the chicken was fresh and tender.The fatty acid content meets the ideal standard for fatty acid intake recommended by the American Heart Association.