Abstract: Traditional RMR rock mass quality classfication do not consider the effect of in-situ stress.The IRMR rock mass quality classfication which have considered the effect of in-situ stress and made the correction had been applied in the three middle's roadways and stopes of -510m、-555m、-600m in Sanshan island gold mine. Compared with the results of RMR rock mass quality classfication,we can find that most results of IRMR rock mass quality classfication are worse than former,but the rock mass quality of -510 travelling roadway,553^# stope and 601^# stope are at the same level in two evaluation system.So,it is more safe in tackling high in-situ stress rock mass engineering using IRMR rock mass quality classfication,and it more resonable and effective.We had used the IRMR grade to determine the rock mechnical parameters in all the three middle,it can provide a basic evidence for numerical simulation study on optimization of the structural parameters of the deep stope and engineering disaster prevention and control,and so on.