In this paper, the authors' recent developments on the crack propagation analysis software system are presented. The system has been developed based on three main parts i) finite element model generation, ii) finite element analysis and iii) stress intensity factor computations. We adopt the quadratic tetrahedral finite element and the processes in the finite element model generation are fully automated by using the Delaunay tessellation technique. The stress intensity factors are evaluated by using the virtual crack closure-integral method (VCCM) for the tetrahedral finite element. In previous papers, the authors have presented the crack analysis software system for single crack cases. It is extended to deal with the propagations of multiple cracks and their coalescences. The net-section yield criterion is adopted to judge the coalescence of adjacent cracks. In this paper, a brief review on the exiting crack propagation analysis system is presented first and present developments for the multiple cracks with their coalescence are discussed in detail. Finally, some numerical examples are presented.