In order to investigate the effect of sodium carbonate injection on tenderization and quality of air-dried beef, the pH, shear force, water content, water activity, yield and sensory quality of air-dried beef injected with different concentrations of sodium carbonate (0,0.25,0.30,0.35,0.40mol/L) were measured. The results showed that increasing the sodium carbonate concentration, the pH value, water content, water activity,yield and tenderness of air-dried beef were significantly elevated, the shear force was decreased. However, when sodium carbonate concentration was over 0.35mol/L, the sensory quality and chewiness of air-dried beef became worse and had a certain degree of alkali flavor. According to correlation analysis, there was a significant positive correlation between pH and tenderness, water content, water activity and yield of air-dried beef (P<0.01). Therefore, the effect of sodium carbonate injection on air-dried beef tenderness was mainly related to the change of pH in meat. The results indicated that sodium carbonate injection could effectively improve the edible quality of air-dried beef. This effect was best at the concentration of 0.35mol/L. And this condition, the shear force could be reduced by 33.67%, and the yield increased by 12.05% to 45.12%, and the change of pH value was the main reason for the improvement of air-dried beef tenderness and quality by sodium carbonate injection.