Abstract: It is challenging for shield tunnel construction when spheroidal weathered granite body is encountered, and controlled blasting could be adopted as a pretreatment measure. In this paper a numerical simulation calculation was conducted by FEM ANSYS regarding controlled blasting of the spheroidal granite weathered body, the blast vibration and rock breaking effect were analyzed. The results show that the vibration velocity of the ground right above explosive is 0.35 cm/s after blast treatment, meeting the requirement of the specification of blast construction;good rock breaking effect is obtained for the spheroidal weathered granite body under the effect of blasting, and the max. size of the broken rock is 6.71 cm, meeting the mucking requirement for shield driving.