When stricken by a catastrophic natural disaster, emergency rescue operation is very critical to many lives. Many people trapped in the disastrous areas under collapsed buildings or landslides may have a large chance to survive if they are rescued in "Golden 72 Hours". People evacuated from their home jammed in highways or dome shelters need to communicate to each other for various reasons. However, communication systems were usually down due to various reasons. The loss of communication systems made the rescue operation extremely difficult. Many people died before they got a chance to be rescued. This paper analyzes the causes that paralyzed the entire communication systems in Jiji Earthquake and proposes a MANET based emergency communication and information system that can support a large number of rescue volunteers under catastrophic natural disasters.