Aiming at the problems of low production capacity, many cutting works, high cost, poor working environment, many safety hazards and high risk in the mid-section quarry of 2 230 and 2 170 in Pakrut Gold Mine, the study has obtained a reasonable size of the quarry by adopting Mathews' stabilization graphic method on the basis of rock physical and mechanical property tests and RMR (rock mass geomechanical classification). On this basis, the mine was changed from 4 low sections of 12 m to 2 high sections of 21 m. Taking the mining width as a variable, the FLAC3D software was used to simulate the stability of the mine under the condition of "mining in three intervals", and the optimal width of the mine was determined to be 11-12 m. Finally, through the industrial test, the collapse of the optimized mine was analyzed, as well as the economic and technical indexes; The results show that the production capacity of the optimized quarry is increased by 20%, the loss rate is reduced by 4.67 percentage points, the depletion rate is reduced by 3.25 percentage points, the kiloton mining and cutting ratio is reduced by 36%, and there is no collapse phenomenon in the quarry, which is up to the expectation. The study shows that the optimization method of structural parameters of the quarry based on rock physical and mechanical property test and RMR rock classification, Mathews stability graphical method and FLAC3D numerical simulation, and finally verified by industrial test has high application value.