In combination with the practice and the blasting features of ore/rock in Wohushan Open-pit Iron Mine, some indices of evaluating the blasting effect are presented, such as boulder yield,the consumption of unit explosive, the blasted volume per meter-of-hole and the efficiency. of electric shovel. In order to improve the blasting effect, a series of measures are taken, such as fixing reasonable blasting parameters, employing space loading structure, controlling detonating sequence and short-delay time of blasting, hence to effectively control boulder yield and increase the efficiency of electric shovel, decrease the blasting cost.