The stratigraphic breaks and unconformities in the Philippine Sea region are analyzed by the ship "Glomar Challenger" well data and sections of surrounding islands. The comparison with P. Veil's scale of global cycles of relative sea level changes of different orders is performed. The manifestation of three impulses of tectonic activity and five impulses of volcanic activity is established in the region. The conclusion is made that formation of unconformities in the region is determined by a complex combination of tectonic, volcanic processes and global eustatic changes of sea level and connected with glaciations in some periods.