Abstract: Aiming at the problem of large section roadway occurred "pumping gun", bad forming, over-break over-excavation phenomenon during rock blasting, a double pair of wedge mixed cut ways, depending on the strength of rock excavation section and the surrounding eye, caving eye parameters formula, the surrounding eye, caving eye spacing, minimum line, the amount of the drug is accurately calculated. Engineering practice showed that the optimized smooth blasting parameters improved cut blasting and mucking efficiency, roadway shape was better, which reduced the damaging effects of the surrounding rock.