In Asian Financial Crisis during the end of 1990s, millions of people lost their money in one day, international investors were reluctant to lend to developing countries, leading to economic slowdowns in developing countries in many parts of the world. This paper will talk about how the crisis become, speculators how to speculated the financial market, a case in HK how to defeat speculators attack, and IMF provided support package for rescuing attacked countries. We hope our paper can give some ideas to people and show the importance on balancing the domestic economy to avoid the crisis happen again.