The effects of different fertilization treatments(T1，organic fertilizer；T2，organic fertilizer+microbial agent；T3，microbial agent；CK，control)on the intrinsic quality，respiration rate，fruit hard and brittleness related enzymes and gene expression of apples after bag removal were studied by using the 5-year-old‘Starkrimson’apple fruit trees as materials.The results showed that the application of organic fertilizer containing microbial agents significantly increased the soluble solids，soluble sugar and sugar to acid ratio of the fruit compared with the traditional single application of organic fertilizer.The fruit respiration rate and ethylene release rate increased significantly from 0～12 days after bag removal，and stabilized at 12～15 days.On the 9th，12th and 15th day after fruit bag removal，the content of soluble solids in T2 treatment was 2.63%，5.89% and 8.78% higher than that of CK；the soluble sugar was 6.89%，6.71% and 12.86% higher；the ratio of sugar to acid was 15.85%，19.25% and 17.08% higher than that of CK，and the difference was significant.The T2 treatment significantly increased the aroma content of the fruit，and the total aroma content of the apple fruit was 16.69%，9.06% and 6.25% higher than that of CK，T1 and T3，respectively.The organic fertilizer applied with the microbial agent is beneficial to coloring the apple fruit after bag removal，so that the pericarp cells are arranged closely and neatly，which plays an important role in improving fruit fragility and slowing down the fruit hardness.Through the cell wall enzymes PME and PG activities，the cell wall enzyme activity of the fruit was increased after the bag was removed.The T2 treatment of PME，PG activity and relative gene expression were lower than CK treatment，so the fruit maintained higher hardness and brittleness after bag removal.In summary，the treatment of organic fertilizer containing microbial agents has an important role in improving the fruit quality of ‘Starkrimson’ apples after bag removal.