Disaster Emergency Communications (DEC) is one of the core mechanism for disaster response. DEC not only an critical information channel for the government, but also an key path for news media and the general public. the typhoon Morakot flood in 2009 to prove again that DEC is the key for government to response a major disasters . If the DEC can not be activated just in time, then disaster relief resources can not be quickly dispatching, inter-institutional linkages can not be effectively coordinated, the media declared advocacy, people panic anxiety, the result will not only affect the government's disaster relief policy, even more likely to paralyze the entire government mechanism and cause a major political crisis! It becomes a critical challenge that the public communication networks may destroy in disaster. In this article will explore the United States, Britain, Japan, China, and Taiwan's DEC systems. A DEC's comparative analysis and recommendations will be offered also.