Ⅰ.Introduction In recent decades,with the rampancy of transnational organized crimes,especially the expansion of terrorism,international police cooperation has been attached great importance to by international organizations and various countries and become an atout to maintain national security and core interests.Inter-state criminal cooperation is diverse.It can be police cooperation,reciprocal judiciary In recent decades, with the rampancy of transnational organized crimes, especially the expansion of terrorism, international police cooperation has been attached great importance to by international organizations and various countries and become an at out to maintain national security and core interests.Inter- state criminal cooperation is diverse. It can be police cooperation, reciprocal judiciary