Abstract: The emission characteristics of PM_2.5 in coal-fired power plants and the current main emission testing methods for PM_2.5 were introduced. The relatively mature monitoring methods included Method 201 A, Method 202 which were developed by US EPA and ISO 23210:2009 method which were developed by ISO. The dilution sampling PM_2.5 emission test methods and ELPI method show good development and application prospect in recent years. Finally, combined with the pollution controlling experience in China, some suggestions on air pollutants emission reduction from coal-fired power plants were raised.