Manifold Method provides a unified framework for solving problems with both continuous and discontinuous media. In this paper, by introducing a criterion of crack initiation and propagation, the second order manifold method is used to simulate two-hole blasting and Hopkinson spalling of rock. In the study of two-hole blasting, two different initiation conditions are considered. One is simultaneous initiation, the other is 0.1 ms delay initiation. The whole blasting process including crack initiation, crack growth and fragment formation is simulated. In the study of Hopkinson spalling, the propagation and interaction of stress waves and the spalling process caused by a reflected tensile stress wave are reproduced. The simulation results including the thickness of the formed scab and its velocity are in good agreement with theoretical values. Manifold method proves to be an efficient method in the study of dynamic fracture of rock.