Abstract: Based on the engineering research background of No.56 steeply inclined thin ore vein in Jinchanggouliang Gold Mine，the optimization of medium-deep hole blasting parameters is carried out by using LS-DYNA numerical simulation and field industrial test. According to the actual engineering condi⁃ tions of the mine，the numerical model of ore body blasting is constructed，and the material constitutive and state equation parameters of rock emulsion explosive，air and ore rock are set. The simulation and opti⁃ mization of hole spacing，row spacing and single initiation row number are completed step by step. The re⁃ sults show that when the blasting parameters of hole spacing of 1.6 m，row spacing of 1.0 m and three rows of one-time blasting are adopted，the energy distribution of explosives is uniform，the effective stress distri⁃ bution around the blasthole is reasonable，and there is no excessive crushing or large block phenomenon. The effective caving of ore body can be realized，and the overall blasting effect is good. Based on the numer⁃ ical simulation results，the industrial test is carried out. The parameter scheme of hole diameter 60 mm， hole depth 7.4 m，hole spacing 1.6 m，row spacing 1.0 m and one blasting three rows is adopted. The sur⁃ rounding rock is stable and the ore block is suitable after on-site blasting. The three-dimensional laser scanning calculation showed that the ore loss rate in the goaf is only 2.04%，the dilution rate is 27.29%，and the comprehensive blasting effect is good. The blasting parameters determined in this study are suit⁃ able for the mining demand of steeply inclined thin oreveins in Jinchanggouliang Gold Mine，and also pro⁃ vide theoretical reference and technical reference for the medium-deep hole blasting mining of similarore veins.

Key words: steeply inclined thin ore vein, medium-deep hole blasting, LS-DYNA, numerical simu? lation, blasting parameter optimization