Reasonable support is one of the important means to control roadway stability and deformation,while engineering rock mass quality evaluation is an important basis for determining reasonable support scheme.In order to solve the problems of simplex support mode,low support efficiency and high support cost in a copper mine,Q system and RMR method are used to grade the rock mass quality of 4 engineering rock groups in the mine.Based on the support diagram of Q system,and the factors of mine support technology and construction conditions,the graded support scheme and support parameters are formulated and optimized,and the reasonable support time is quantified by using the self-stabilization time of unsupported rock mass of RMR method,so as to guide the on-site support construction.The result of engineering practice shows that the graded support scheme is good,not only meeting the safety requirements of roadway,improving the construction efficiency,but also reducing the support cost by 2 million-3 million yuan/a.