The differences were studied including color, tenderness, pH, protein degradation, and other indicators of beef and mutton at the best slaughter ages of cattle and sheep and the high and low-grade parts of the meat. Samples of longissimus dorsi (YH, NH) and abdominal muscles (YL, NL) of post-mortem Qinchuan beef and horizontal goat meat were taken for determination of pH, color, shear, sarcoplasmic and myofibrillar proteins, the solubility and degradation polymerization conditions. The results shown that the pH value of YL was significantly higher than that of YH (P＜0.05), there was no significant difference between the two parts of beef (P＞0.05), the pH value of mutton at the same part was significantly higher than that of beef (P＜0.05). The L^* values of the longissimus thoracis of beef and mutton were significantly higher than those of the external intercostals. The a^* value of YH was higher than that of YL, and the b^* value of NH was higher than that of NL (P＜0.05). The L^* value of mutton at the same part was significantly higher than that of beef. The a^* value of NL was greater than YL, and the b^* value was less than YL (P＜0.05). The shear force and myofibrillar protein solubility of the longissimus thoracis of beef and mutton were significantly less than that of the external intercostals, and the sarcoplasmic protein solubility was significantly greater than that of the external intercostals (P＜0.05). The mutton shear force and myofibrillar protein solubility of the same part were significantly lower than that of beef, and the sarcoplasmic protein solubility was significantly greater than that of beef (P＜0.05). The tenderness and color of the horizontal goat were slightly better than that of the Qinchuan beef. The degradation of the protein was slightly higher than that of the Qinchuan beef. The length of the longissimus dorsi of the cattle and sheep was better than that of the abdominal muscles, and the degree of protein degradation was higher than the abdominal muscles.